During the contest the 15% addresses trades on stocks with wacky spreads, and the new dollar volume rule for eligible stocks further limits how often this might occur, especially in initial picks.
Mechanically, I think it would be almost impossible for Len to capture accurate ask prices AT THE CLOSE for the several hundred stocks in the contest. Over the weekend the bids and asks shown are the "walk away" numbers MMs set to snag stray market orders that come in--they are not meaningful.
It might make sense to have a rule that says something to the effect of "initial picks will be valued at the first trade price, if higher than the Friday close, for stocks that trade less than $5,000 worth of shares on the first day of the contest". That would focus the changes on the stocks with outlandish spreads, as opposed to stocks that happen to make a legitimate big move on day 1, and would be easy to find and isolate over a relatively small population of stocks. This would also align with the intent of the dollar volume rule.
btw--the contest can still be a lot of fun even if you would personally change the rules in some way or another. Play the game!
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