I think you are a bit unnecessarily pessimistic. I would like to think that steroids are not used at the Premiership level, certainly not on an approved basis. Have there been any rumours of this? If so, it would put a certain club's imaginative accounting in the shade.
As for jinking, sidestepping runs, did you watch the Falcons/Quins game? Here are the two tries scored by Tyrone Green:
I just hope he's not Welsh!
Nope South African import.
The SRU are busy checking if his granny ever ate a piece of shortbread