Not sure what you’re saying is a random idiom, but if you mean ‘tap out’ is about as random as ‘flip the bird’, then that seems wrong to me. “Flip the bird” sounds like a fairly random phrase, closer to the randomness of cockney rhyming slang where the literal meaning has no relation to the new meaning (e.g. to go ‘up the apple and stairs’ means to ‘go up the stairs’, just because it rhymes). “Tapping out” refers to literally tapping your combat partner, which itself is a very natural choice of protocol, because you often cannot speak while you are being choked, it is not a random choice of action nor is the description somehow random.
Not sure what you’re saying is a random idiom, but if you mean ‘tap out’ is about as random as ‘flip the bird’, then that seems wrong to me. “Flip the bird” sounds like a fairly random phrase, closer to the randomness of cockney rhyming slang where the literal meaning has no relation to the new meaning (e.g. to go ‘up the apple and stairs’ means to ‘go up the stairs’, just because it rhymes). “Tapping out” refers to literally tapping your combat partner, which itself is a very natural choice of protocol, because you often cannot speak while you are being choked, it is not a random choice of action nor is the description somehow random.
Yeah the fact that the idiom only really existed in this particular context and wasn’t random is fairly compelling.