I apologize in advance for anything I write below that is unclear. I have to start work in a moment and Im hurrying to get this written.

I recently have repeatedly seen arguments back and forth about how to gauge Mendenhall's performance given recruiting. As part of that discussion the average class rank of BYU being well below the Poll performance is often used to argue BYU has outperformed their recruiting. That argument only makes sense if we know the class ranking of the teams BYU has played. I have used Blue Cat's formula for measuring the talent on a team by averaging the recruit ranking for that year and the previous 4 years. This makes sense to me for evaluating total team talent because it gives you input from each class that is potentially part of the team. One could weight the averages based on the average contribution a class gives in terms of starters but this already took enough of my time. There are plenty of criticisms that are valid in terms of how recruiting sites do their rankings but I think this gives us at least a rough measure of how teams performed based on recruiting.

I used both Scout and Rival rankings. To predict a win vs a loss I compared the average class ranking of BYU to the opponent average class. Whomever had the hire average ranking was predicted to win. A better way of doing this would have been to compute confidence intervals for each average class ranking but Im ok with this being a rough estimate. I also did not account for home vs away.

Example: BYU's 2006 team received a 5 year average class ranking of 59.9. (Rivals 68, Scout 51.8) This was computed by taking the average from the data below:
2002--36--46
2003--109-59
2004--65--55
2005--63--53
2006--67--46

BYU's record since 2006 is 81-32
BYU's predicted record based on the average class rank from both Rivals and Scout is 82-31
BYU's predicted record from Rivals only 74-39
BYU's predicted record from Scout only 87-26

These results indicate that while any one game is not accurately predicted by rankings the team record over time is pretty well estimated by the ranking.

A few interesting results:
BYU was predicted to go 5-3 against Utah with 3 straight losses

Performance against Power Teams: BYU was predicted to go 1-31 but actually went 16-16. Two things combine to explain this in my opinion. 1. BYU gets up for games against power teams. 2. Power teams are overrated in their class rankings on average.

Best Wins: 1.Texas 2013 2.Oklahoma 2009
Worst losses: 1. USU 2010 2. USU 2014


Below are the results for each BYU season from 2006 on (the first year with 5 years of class rankings)


2014---------------Avg-----Rivals-----Scout-----Result
Uconn--------------W-------W----------W---------W
Texas--------------L---------L-----------L----------W
Houston-----------W--------L-----------W---------W
Virginia------------L---------L-----------L----------W
USU---------------W---------W----------W---------L
UCF---------------W---------W----------W---------L
Nevada-----------W---------W----------W---------L
Boise State-------W---------W----------W---------L
MTSU-------------W---------W-----------W--------W
TOTAL: Avg 7-2 Rivals 6-3 Scout 7-2 Result 5-4

2013---------------Avg-----Rivals-----Scout-----Result
Virginia------------L---------L----------L----------L
Texas--------------L---------L----------L----------W
Utah---------------L---------L----------L----------L
MTSU--------------W--------W---------W---------W
USU----------------W--------W---------W---------W
GT-----------------L---------L----------W----------W
Houston-----------W--------W---------W---------W
BSU----------------W--------W---------W---------W
Wis----------------L---------L----------L----------L
ID ST--------------W--------W---------W---------W
ND-----------------L---------L----------L----------L
Nevada------------W--------W---------W---------W
Wash--------------L---------L----------L----------L
TOTAL: Avg 6-7 Rivals 6-7 Scout 7-6 Result 8-5

2012---------------Avg-----Rivals-----Scout-----Result
Wash St-----------W--------W---------W---------W
Weber-------------W--------W---------W---------W
Utah---------------L---------L----------L----------L
BSU---------------W--------W---------W----------L
Hawaii-------------W--------W---------W---------W
USU---------------W--------W---------W---------W
OSU---------------L---------L----------W---------L
ND-----------------L---------L----------L----------L
GT-----------------L---------L----------L----------W
Idaho-------------W--------W---------W---------W
SJSU--------------W--------W---------W---------L
NMST-------------W--------W---------W---------W
SDSU-------------W--------W---------W---------W
TOTAL: Avg 9-4 Rivals 9-4 Scout 10-3 Result 8-5

2011---------------Avg-----Rivals-----Scout-----Result
Miss----------------L--------L----------L----------W
Texas--------------L--------L-----------L----------L
Utah---------------L--------L-----------W---------L
UCF----------------W-------L-----------W---------W
USU----------------W-------W----------W---------W
SJSU---------------W-------W----------W---------W
OSU----------------L--------L-----------W---------W
IDST---------------W-------W----------W---------W
TCU----------------W-------W----------W---------L
Idaho--------------W-------W----------W---------W
NMSU--------------W-------W----------W---------W
Hawaii-------------W-------W----------W---------W
Tulsa---------------W-------W----------W---------W
TOTAL: Avg 9-4 Rivals 8-5 Scout 11-2 Result 10-3

2010---------------Avg-----Rivals-----Scout-----Result
Wash--------------L---------L----------L----------W
AF-----------------W--------W---------W---------L
FSU----------------L---------L----------L----------L
Nevada------------W--------W---------W---------L
USU---------------W--------W---------W---------L
SDSU--------------W--------W---------W---------W
TCU----------------W--------W---------W---------L
Wyoming----------W--------W---------W---------W
UNLV---------------W--------W---------W---------W
CSU----------------W--------W---------W---------W
UNM---------------W--------W---------W---------W
Utah---------------W---------L---------W----------L
Utep---------------W--------W---------W---------W
TOTAL: Avg 11-2 Rivals 10-3 Scout 11-2 Result 7-6

2009---------------Avg-----Rivals-----Scout-----Result
OU-----------------L---------L----------L----------W
Tulane-------------W--------W---------W---------W
FSU----------------L---------L----------L----------L
CSU----------------W--------W---------W---------W
USU----------------W--------W---------W---------W
UNLV---------------W--------W---------W---------W
SDSU--------------W--------W---------W---------W
TCU----------------W--------W---------W---------W
Wyoming----------W--------W---------W---------W
UNM---------------W--------W---------W---------W
AF-----------------W--------W---------W---------W
Utah---------------W--------L----------W---------W
OSU---------------L---------L----------W----------W
TOTAL: Avg 10-3 Rivals 9-4 Scout 11-2 Result 11-2

2008---------------Avg-----Rivals-----Scout-----Result
UNI----------------W--------W---------W---------W
Wash---------------L--------L----------L----------L
UCLA---------------L--------L----------L----------L
Wyoming----------W--------W---------W---------W
USU----------------W--------W---------W---------W
UNM---------------W--------W---------W---------W
TCU----------------W--------W---------W---------W
UNLV--------------W--------W---------W---------W
CSU----------------W--------W---------W---------W
SDSU--------------W--------W---------W---------W
AF------------------W--------W---------W---------W
Utah---------------W---------L----------W---------W
Arizona------------L----------L----------L----------L
TOTAL: Avg 10-3 Rivals 9-4 Scout 10-3 Result 10-3

2007---------------Avg-----Rivals-----Scout-----Result
Arizona------------L----------L----------L----------W
UCLA--------------L----------L----------L----------L
Tulsa--------------W---------W---------W---------L
AF-----------------W---------W---------W---------W
UNM--------------W---------W---------W---------W
UNLV-------------W---------W---------W---------W
E Wash-----------W---------W---------W---------W
CSU---------------W---------W---------W---------W
TCU---------------W---------L----------W---------W
Wyoming---------W---------W---------W---------W
Utah--------------W---------L----------W---------W
SDSU-------------W---------L---------W----------W
UCLA--------------L----------L----------L----------W
TOTAL: Avg 10-3 Rivals 7-6 Scout 10-3 Result 11-2

2006---------------Avg-----Rivals-----Scout-----Result
Arizona------------L----------L----------L----------L
Tulsa--------------W---------W---------W---------W
BC-----------------L----------L----------L----------L
USU---------------W---------W---------W---------W
TCU---------------W---------W---------W---------W
SDSU-------------W---------W---------W---------W
UNLV--------------W---------W---------W---------W
AF-----------------W---------W---------W---------W
CSU---------------W---------W---------W---------W
Wyoming---------W---------W---------W---------W
UNM---------------W---------W---------W---------W
Utah---------------W---------W---------W---------W
Oregon------------L----------L----------L----------W
TOTAL: Avg 10-3 Rivals 10-3 Scout 10-3 Result 11-2

Google Spreadsheet with data
https://docs.google.com/spreadsheets/d/1lwJfn6F2-ugZHvD61Hzv2e_7FFwcWHjOp6Mj_jIY-34/edit?usp=sharing