sp_ has brought my 750ti cards from 5.5+ Mh/s to 6.1Mh/s mining Quark within the last 20 releases.
Before I started 1 year ago quark was doing 4.5 on the 750ti, you can compile djm34's version here and test for your self:
https://github.com/djm34/ccminer-standardSolomining works, but my release 68 is 45% faster.