We have an option for installing with the default names, in which case `gtar` won't be available. You might want to conditionally apply this change based on how gnu-tar was installed, though I suppose that would break if the user reinstalled tar without the option.

git in Tigerbrew applies a bit of a hacky workaround for this: https://github.com/mistydemeo/tigerbrew/blob/master/Library/Formula/git.rb#L47-L54