using oldest date when squashing commits

moin,

during interactive rebasing, i sometimes find it necessary to move a hunk from one commit to a later one in the branch. now, if that hunk cannot be re-ordered with the later commit due to conflicting with it, it becomes necessary to squash the later commit onto a temporary commit created from the extracted hunk, not the other way around (or using a stash). unfortunately, this causes the author date of the later commit to be reset, which can rather seriously falsify the date if the branch is long-lived.

i know how to manually work around that, but that's not exactly user friendly.

my first thought was to create an --oldest-date option (essentially complementary to --ignore-date).

but i wonder whether it even needs to be an option? why would anyone not want that behavior, unless they are explicitly resetting the date anyway?

thanks