I agree 100% on the utility of a 4 panel diff, but I'd be careful using kdiff3... I also used it for quite a while but found that it would "auto resolve" some merge conflicts which git would flag, and I found it would sometimes auto resolve them wrong (maybe about 10-20% of the time?), and I couldn't figure out how to turn this feature off... I'm using tortoise git merge now (which also does do some auto resolve but only simpler resolutions)
According to `kdiff3 --help`, there's a flag --qall "Do not solve conflicts automatically.".
I've not noticed the problem you describe, so can't confirm whether it is solved by that flag - a while ago I mostly switched to Sublime Merge from kdiff3.
