I have never taken the one-move only rule as legalised blocking - weaving across the track several times would be blocking.
My take on the one-move was that it allows the lead driver one attempt to break the tow effect of the car behind, but if that fails he is not allowed to make any other 'blocking only' movements.
It's not a lot of difference to what Kewee is arguing with regard to allowing drafting/slipstreaming only, but with the driver in front being allowed the single choice of movement, invariably going off line, if he wants to take that risk.
As to the DRS and Pirelli tyres situation at this point in time, I consider it to be a case of 'be careful what you wish for'.
It's not long ago many were complaining about processional F1 with overtaking nigh on impossible, allegedly, although the best still managed to do it - now it's complaints that it's all too easy to pass, which is what was being wished for. 
OK, it may have gone too far this season, but the same voices demand that every season must be better than the one before. 
Thankfully, today's news reports seem to signal some sanity, and have stopped a move-the-goalposts knee jerk reaction.