Not going to read all this, but my opinion goes along with online play...
a sitting out player is considered in "check" mode until aggressive action gets to him/her, then fold to any bet.
EX: player sitting out is in big blind...a couple limpers, absent bb checks (hand is still live). Flop checks around, player's hand is still live, and checks the turn automatically. One of the limpers bets, action back to sitting out player, NOW they fold.
Ex2: Same as above but limpers check it down, BB hand is LIVE and can win the pot.