Yabut, that's not my experience. I can't speak to the OP's query, but I'd like to knowfro you, the reasons you say XP doesn't require any kind of registry repair? Repairing the Registry in both Home and Pro can speed up a lot of things, especially when it becomes full of bad shortcuts, leftover program segments, unaware of files that have been legitimately moved, or deleted (not as in manually uninstall), and so on for a very long list of possibilities. The Registry can easily grow to many magnitudes its required size, without being "broken" aka non-functioning, and cleaning (aka repairing) it up is definitely worth while.
However, if I am missing something, I would like to hear your thoughts on the matter. I don't intend to get into a philosophic debate, so please be clear and consice, with references wherever possible.
TIA,
Pop