It's not as much a phobia, as it just hurts my god damn ears! lol
Whatever guys do in their bedroom is their business. Like I said previously, if that is all they plan on doing, Dr_simon's first reply is all the advice they'll ever need.
Don't get me wrong, I understand why bands detune. It can be very effective, and most recording artists seem to pull it of. I guess my point was that tuning low isn't a guarentee for sounding heavy, since a big part of it depends on how the guitarsound works with the rest of the band.