The latest git version will limit the size of the thread concurrency if you only git it --shaders alone, so it might be worth doing that and setting max allocation to 100%.
and testing lower than maximum TC is worth checking out
I found that my best hash rate came with max allocation 80 and -g 1 on a 5850 ... cgminer sets TC 5760 instead of 7200
Now I am running with max allocation 100, --thread-concurrency 5760 -g1 and my rate is 277 Kh/s (tc 7200 gives 257 Kh/s)
p2pool's rate estimate confirms the reported speed, so I think that I found my optimum
btw my earlier report of good hash rate with max allocation 40 / 50 was erroneous: 2 GPU Threads with TC 2880 produced many invalid shares reported by p2pool but they were counted as accepted shares in cgminer
(lowering intensity eliminates the invalid shares but reduces hash rate)
time to switch my other machines to LTC mining (cards 5870, 6790 and 2 different AMD APUs to optimize *lol*)
