If not, perhaps save it up for awhile, until you can knock it out.

If you can't pay it off all at once, then you may cripple your liquidity while at the same time keeping the mortgage obligation, which negates the benefit of paying it off. Worst of everything.

I do think the Dave Ramsey approach works (baby step 6 I think) because the higher emergency fund (step 3) does help with avoiding liquidity risks while paying it off.