it's funny b/c in my mind i see Peter's proposal as better than Sidechains for now.  but i should reserve judgment until there's more info.  if endentyrell is to be believed, however, there is much complexity involved in setting up Sidechains that could put Bitcoin in jeopardy.  Adam has admitted that there is risk in being caught in a Sidechain during an attack.  this automatically makes those BTC less valuable on the open market than those on the mainchain.

Spin-offs would be much safer, simpler, and cheaper if it works as a way to deal with altcoins/altschemes.