Just downloaded the latest IC2 and began to toy around with the scaffolding (I have TMI), and noticed something odd.
If I were to place one scaffolding (right-click), and then went to break the scaffolding while I had the item still in hand (left-click) and another block was placed on top of the pile.
I don't know if this a bug or feature (fast construction), but I figured I might as well post it up to double check.