K-Lo,
Based on the differring opinions of just a few of us, to me it just points out how weak some of the rules are written. You can go any number of ways with your ruling and point to a TDA rule that justifies whatever call you make!
K-Lo has mentioned it eairlier and I've echoed the same feeling on many other posts...the reputation of the player and the intent of the player must be considered. An unintentional call, or raise, that is obviously a mistake should be adjusted.
We always speak of the lesson that will be "taught" the hard way, to the new inexperienced player that doesn't pay attention, or is not quite clear of the action in front of him. Why not ask some of the players that are attempting to steal the pot by raising how they feel about your decision? The floor ruled that your raise was called by a player that really had no intention of calling but is forced to. He didn't want to call your all-in, but the decision of the floor just changed the outcome of the tournament . Think about it. If that were you, wouldn't you like to say; "oh that's okay, he doesn't have to put in the call! Please don't let him call,
please!"
K-Lo, I wanted to address your last situation where the player puts in the 5000 chip...Wow, that does change things doesn't it? I think in a multy handed pot,(which is the situation in the original post) with other players still to act, the player could be locked-in to the 1200 call. The difference is the oversized chip covers the amount of the raise.