can git-describe learn first-parent behavior?

This seems like it would be a rather useful feature. Suppose a maintenance branch, maint/v1.0, is forked from master, and the branch point is tagged something like "v1.0-stable". The next commit on master is tagged "v2.0-base", indicating that it is the first commit of the new release. Suppose two releases are made - a release for public consumption of version 1.0, and a release for internal testing from master (currently 2.0), and we want to embed the output of git-describe into the builds. If bugs were fixed on 1.0, and then 1.0 was merged into master, it seems perfectly possible to run git-describe on master, but get the v1.0 tag in the output.

Is this just a poor workflow? Am I using git-describe incorrectly? Or, does a first-parent option to git-describe seem useful?

Thanks for the input.

Josh