Bus Safety Stop

I have begun to find that it is quite fun to play around with twitter and that it is an interesting way to bug TriMet about little things when I think of it. Riding my regular route from home to school and back again I have always seen those little signs under or above the initial bus stop sign saying 'Bus Safety Stop'. Some drivers ignore them completely, some drivers stop at a few of them (or it could just be to let traffic go by....let's just leave it as a two for), and some drivers (often to my surprise) actually stop at all of them. I poked at TriMet on twitter one morning while commuting for an answer. I didn't expect to get much of an answer, but to my surprise I got this:

Safety Stops have been created on routes where bus vibration may cause damage to private property or utilities or to keep speeds low on severe inclines. ~TriMet

And now, apparently, we know what safety stops are! And why 99% of 51 stops to Portland have the safety stop sign. According to TriMet at least. But I'm just surprised I got an answer in the first place