OC's have more flexibility to avoid certain players. Now in the case of safeties, the goal is to try and establish the run so you can get those speedy safeties cheating up. It's the only way you are successfully going over the top on BYU. Few have this year. But part of them not being seen is because the OC/Offense DOES see them and is again, either running a lot (Houston & Troy) in hopes of going over the top. Houston did in fact have success with this approach until BYU went from an 8 man drop back to 6.5 (spy had QB Run cover and TE support). Ideally, the safeties are the least bruised, fewest tackles required guys on the d-side of the LOS.