True enough. I guess you might also want to keep a record of the patch that removed it, so you can backport it to the next LTS kernel (or the latest one, but that's more of a moving target, so might bite you) once this one drops support.
Do you know how we could fix that? I could only find the Xen wiki page on power management and it seems to be mostly about CPU frequency throttling? I also don't know anything about throttling on the Pyra, but if we have the usual Linux throttling support, Xen throttling shouldn't be too far off, right?