I work on a project with 3 other devs; an xcode conflict is an "oh, bummer" moment, but not a hairpuller. 90% of the time we've both added files, and the merge is as easy as "choose both."

It's still the sort of thing where you want to check out, change the project, and check back in quick to avoid conflicts. I can imagine it getting worse with far-distance branches though.

It's not too different from a makefile, except you'll get a better error message when you muck up your makefile.