Curious that I should happen upon this thread as I have just played about 10 days of poker in 3 different smaller poker rooms in Nevada over the last month, and these and many other rules came into question over and over again. I actually had the dealer, twice in the span of one hour, grab my hand from in front of the rail and muck them when i had given no indication of folding. I was in the number one seat and the muck pile was on the other side of a rake drop with my cards sitting by my stack within 2 inches of the table rail. she informed me that unless I have a card protector, she can grab my cards and they are dead once she does. Later that night, the same dealer grabbed my folded cards, that i had tossed just in front of the muck pile, and showed them to a player who asked to see them without asking me. I was also told at this same table that my cards will immediately become dead if any other players cards or muck cards come into the slightest contact with my live hand if I don't have a card protector on them. Also at the same table, different dealer, different night was told that my cards are dead and part of the muck if I push or toss them forward and release them. Frustrating, to say the least, but small casinos in the middle of nowhere and I understand they have a hard time getting quality dealers. I blame the casino staff for not training and requiring all the dealers to know the house rules and having them applied consistently.
I have played in Las Vegas a fair bit and the floor has been called many times and consistently informed players that any cards that touch the muck pile are dead, period, and that once you have folded your cards they are dead period (i.e. you can not grab them off the table and expect them to be live if you made a mistake reading your hand), once the dealer touches your folded cards they are a part of the muck pile, if you verbally indicate you are folding your cards are dead and part of the muck.
I think many of the casinos in Las Vegas have developed and adopted these kind of rules over time to reduce problems and provide consistency to play. I don't know about Roberts rules of poker, but the Vegas rules seem reasonable and consistent.
This being said, if I fold a hand I don't want to show, I just try to make sure they touch the muck or other folded cards and they are dead.
If I called a bet and the hand goes to showdown and I want to see the better cards, I simple make him show his cards first or fold them and give me the pot. If the tries to get away with only showing card (I really hate this kind of ridiculous posturing, slow playing) I sampling say "are you folding, if not then show your cards" If they do fold there cards without showing, then I win the pot and don't have to show my cards and I make sure they hit the muck pile when I turn them in.
I hate the posturing and slow playing that players try to get away with in live play and I really think it is up to the dealers and casinos to just cut trough that crap. Properly trained dealers, after the last card is dealt, usually say "Let's see the", then start with the better and progress around the table in order to define the winning hand. If a player is reluctant to show his cards then the dealer informs that to either "turn em up or fold", then the other players don't have to seem to be a jerk for asking to see what they have.
Sorry for the long post, it just brought up these issues that drive me crazy!! And yes, I want to know what the other player has if i am entitled, especially if i have folded to their aggression on previous hands.