A few of points, Wallettheif. First, the BYOH mod is currently sitting at version 1.82 with numerous fixes, revisions and additions made since it was first released several months ago. Awesome as BYOH is, saying it never had any issues is a little dishonest.
Second, just because you have not had issues does not mean that nobody else has. A lot of people haven't run into any issues with Hearthfire, either.
Finally, Hearthfire wasn't developed by an entire team. It was three or four guys, each of them specialized in what they brought to the table. The guy who handled the scripts missed a condition check. I don't want to make excuses for it, but it's not game breaking and you have to go out of your way to trigger it. That not nearly as bad as the install-corrupting shenanigans you can get from careless modding.