Slipstreaming buses

I had embarassing/painfull incident drafting a bus in Aus. Checked over the shoulder to change lanes, by the time I turned my head around the bus had stopped. My helmet took most of the impact and cracked right through - bike was fine. Doesn't seem to be much point drafting them over here with such frequent stopping.

Same here, Oxford Street, London, bus slowed so I looked over my shoulder to check it was good to overtake, turned back to see a stopped bus . . . . . boof!

No real damage other than shame and embarrassment. :)