I don't think it is appropriate to change a reference, like you say. If two people modify the same code, then you should signify a conflict and have someone res

I don't think it is appropriate to change a reference, like you say. If two people modify the same code, then you should signify a conflict and have someone resolve the issue by hand. There's no machine on earth that can tell whether you meant to call foo() or foo_nolock(). The point is to prevent a false positive (the worst thing by far when merging). If you modify the foo() function and I add a new reference to it, current line-based merge strategies will silently resolve that because our edits appear to be far apart, even though they are semantically conflicting. With some semantic analysis you can determine that manual resolution is much better. The point is to throw a conflict, not change a reference silently.