I don't see how any of the examples, at least as summarized above, describe a "catch the player" or "magic word" situation. In fact, I think the approach described by [MENTION=97077]iserith[/MENTION] is the opposite to a "magic word" gotcha, because he is trying to clarify character actions in the description of what the character does.
If a player says, "I roll [ability] on it," the player is not really describing the actions of his player. If the DM simply takes that 'action' and adjudicates it, without clarification, they're deciding what the character actually did. So, assume we have a cursed altar that reacts on contact with human flesh.
PLAYER: I roll investigation on that altar. Umm ... 11.
DM: As run your hand across the strange grooves of the altar, you suddenly feel an ancient, terrible evil moving up into your hands —
PLAYER: Wait, what? I didn't say I touched it.
DM: You rolled investigation. I described the oddly textured symbols. 11 didn't hit the DC.
PLAYER: ...
DM: Roll a wisdom save. You're being possessed by an ancient evil.
Compare to.
PLAYER: I want to investigate that altar.
DM: How are you investigating it?
PLAYER: Well, I'm going to look at those strange grooves and see what they mean.
DM: They're have a rough, uneven texture, and cut deep into the stone of the altar. You think you can see something brown and rusty in there.
PLAYER: I'm going to see if I can scrape it out with my fingernail.
PLAYER 2: Wait, what?
PLAYER: Yeah, I want to scrape those flakes out with my finger and see what they are.
DM: Ok, when you touch the stone of the altar with your bare finger ...
your example is EXACTLY what i am pointing out... thank you for listing it so i can point out...
In your example, the altar trap as presented is keyed on "does the player say they touch it".
you see it as, and they often portray it as a binary option - either the Gm assumes and the player gets got or the GM waits to see if the player makes a key statement and then the player gets got.
Compare that to a previous example of how i said i would use the SKILL OF THE CHARACTER as opposed to the WORDS OF THE PLAYER to adjudicate this same event.
PLAYER: I roll investigation on that altar. Umm ... 11.
DM: Hmmm... your investigation gets going and you seem some runes, obscured, hard to make out and as you work around the altar an infernal effect manifests and...
PLAYER: uh oh.
and proceed with the effects.
Now again, within the context of the campaign they have alrerady seen cases where they made that check and we got scenes like this...
PLAYER: I roll investigation on that altar. Umm ... 19.
DM: You see the altar is covered in dust and ash with plenty of various runes, some giving you a bad feeling. you notice a lot of dead bugs on the altar and even some bones and skeletons of small varmints that look like they died right there at the base of the altar, the bones piled against it. You see other bits of debris on the altar and resting against the altar too, seemingly unblemished. It has a smell about it, like you have seen at poisoned waterholes or plague houses.
PLAYER: Definitely going to not get up close and personal. Hey, Lou, you recognize these symbols and runes?
See, in this case, its not "you said you touched it" or "you didn't say you touched it" or any key player speak catch phrase or condition that determines whether the good or bad happens, its the skill of the character at doing what was asked - examining the altar and making good choices about how that is done.
If a player has seen both of those outcomes, the fail and zap and the succeed and avoid, they are taught to not get focused on "wish-proofing" their casual play time dialog with the Gm and other players but on making sure their character is being driven in the right directions.