> In fact, one rule of thumb might be that wherever watchtowers are required, a timelocked bribe might be possible.
I think a better heuristic is that, if the logic of the construction assumes "transaction with earlier locktime supersedes transaction with later locktime", then it is timelocked-bribery-vulnerable.
That's true by definition. Timelocked bribes are, well, going to be possible when there are timelocks. I was going more for an "indirect clue" that wherever a watchtower is proposed, a timelocked bribe is possible. This is entirely a pedantic point :-)