I agree. I did buy some OEX puts at the close on friday to hedge the gains in long calls. I can't give you a percentage but I have a rule of thumb that works most of the time. On expiration friday near the close get short or at least long some puts. All the stock that the arbs have bought on thursday and friday to cover positions, will be coming back into the market on monday and depressing it to some extent. Obviously today was exceptional circumstances but check it out next month if you're interested.