Rules are NOT supposed to be up for interpretation; however, it appears that is what is happening here. The Oversized rule states that when a single chip is thrown in without a declaration, then it is considered a call. (my emphasis)
Pokerchip: I understand your frustration, and hence my original post. A few comments though.
You say that the "Oversized rule states that when a single chip is thrown in without a declaration, then it is considered a call", and that the rule should be applied 'hard and fast' and not be subject to interpretation. However, note that the rule as written doesn't say exactly that.
38: Oversized Chip Betting
Anytime when facing a bet or blind, placing a single oversized chip in the pot is a call if a raise isn’t first verbally declared. [...] When not facing a bet, placing an oversized chip in the pot without declaration is a bet of the maximum for the chip.
(emphasis added)
This is TDA Rule 38. There are similar provisions in all the other major rulebooks.
According to a strict reading of the rule, note that the single chip without a verbal declaration is a call only
when facing a bet or a blind. Note that it doesn't say that the single chip without a verbal declaration is a call
always or "in all circumstances". On the contrary - the rule itself provides a very specific condition that must satisfied before the general statement that you gave applies.
So this begs the question: when you are in the BB, and everyone limps to you, are you "facing a bet"? Are you "facing a blind"? Is it clear, and can you apply this rule 'hard and fast'? Note that if everyone limps to you in the BB -- your only options are to check or raise, not to "call" (unless you think 'check' means "call zero", which itself involves a creative "interpretation" of "check").
It is different when someone has put out a bet post-flop and you are faced with the decision to call it or not, or you are not in the blinds and are faced with the decision of whether to call the blind or not pre-flop. In those situations, there actually is a bet or blind to be called.
It has also been pointed out that the rule actually says that
"when not facing a bet", the oversized chip without declaration is the maximum for the chip. When someone checks to you post-flop and you throw out a 500 chip, you are clearly betting 500. You are not "calling zero" there. So when everyone limps to the Big Blind pre-flop, and the Big Blind has no bet to "call" since he can only check or raise, doesn't this part of the rule apply?
And so there we have the dilemma.
I agree with you that rules are ideally clear enough that they need not be subject to "interpretation", meaning that they can be applied strictly. But it's not always as easy as one might think, and that is why when the answer is not clear cut for a given rule, we have to take into account a variety of factors to try to come up with a ruling that would appear to be the most fair --- or put forward a change in the rule so that no "interpretation" is required. In fact, perhaps because of our discussion here, we might see the rule clarified in the future.
For this particular rule, I think one of the big problems is that much of the general public thinks that the rule simply says "single chip = call", because that is easy to remember. And it clearly applies 95% of the time, so there is rarely an issue. But in my opinion, it is an inaccurate generalization of the actual rule. For that 5% of the time where it isn't clear how the actual rule should be applied, because for example we don't know if the BB's option to check or raise can be equated with "facing a bet or a blind", we are left doing what we are doing now -- trying to work out what the ruling should be in a principled and fair manner, and seeing if the majority of experienced TDs will see the problem (and the solution) in the same way.