RE: No substantial action in RRoP
RROP, Sec 3: General Poker, Misdeals, Para 1 states:
1. Once action begins, a misdeal cannot be called. The deal will be played, and no money will be returned to any player whose hand is fouled. In button games, action is considered to occur when two players after the blinds have acted on their hands. In stud games, action is considered to occur when two players after the forced bet have acted on their hands.
RROP Sec 3: General Poker, Betting and Raising, Para 12 states:
12. To retain the right to act, a player must stop the action by calling “time” (or an equivalent word). Failure to stop the action before three or more players have acted behind you may cause you to lose the right to act. You cannot forfeit your right to act if any player in front of you has not acted, only if you fail to act when it legally becomes your turn. Therefore, if you wait for someone whose turn comes before you, and three or more players act behind you, this still does not hinder your right to act.
While the term substantial action is not specifically found in the above, RRoP is describing the same thing when he says that "two players acting" locks in a misdeal, and "3 or more players acting behind you" may cause you to "lose your right to act". The TDA membership has adopted slightly different definitions (2 actions, at least one with chips, or any 3 actions.... thanks to Thomas McGee who proposed this specific terminology in 2011... and the WSOP which I believe was using it by then?), but it's similar in intent to the guidelines in RRoP. The essence of substantial action being that there must be a point, after X amount of action, that there's no going back...