Aye I've read Zainasheff too... pitching rates are on the list of things to pin down, but I've found some over-pitching doesn't hurt the flavour profile of S-05. Activity; yes. Flavour; no. It's already a clean yeast, producing very few esters/phenols, so the added pressure doesn't seem to do jack. Someone with a mass spec could probably demonstrate more accurately, but my perception suggests nothing really changes. A more flavourful yeast would likely be much more sensitive.
Combine that with the fact that I only use the yeast for 1 generation after it's in the packet, and that pretty much blows the whole "yeast will be too tired to re-pitch" thing away too.
I would be interested to figure out how much yeast (in terms of cell count) will be left after brewing say a 1.050 cream ale with a packet of S-05 and washing the trub that remains. I've been meaning to develop a "propagator beer" for growing up yeast whilst also producing a drinkable beer - the cream ale I just did is looking like a good contender.
