I was trapped today by the misdesign of curl command, see bug #449369. So I'd like to remove curl (not libcurl) from my machine. I cannot co that, because git requires it. But it seems that git calls curl only in two places: git-clone.sh and git-ls-remote.sh. Couldn't these two be rewritten so that libcurl would be enough for the whole git. Yeah, this is an enhancement request and I'm not providing the patch (yet), sorry.
Additional info: I mentioned the problem on the git list, and was assured that the last occurence of "curl" command has been removed: http://article.gmane.org/gmane.comp.version-control.git/83640 Consequently, when git-1.5.6 is released and accepted to Fedora, we can drop "Require: curl" and perhaps replace "BuildReuire: curl-devel" by "BuildRequire: libcurl-devel".
Fixed in git-1.6.0.3-1