FWIW, my W saw it as an ultimatum, too. Did it change the marriage? Her behavior? Our SL? No, but it did prompt her to contact a MC.
And, come to think of it, me saying "IWNLIASLMF" did end up enriching the life ... of the MC.
My view is that saying it can be a cage-shaker, and can open a dialogue on the issue, and can let the LD spouse know in fairly clear terms that this is a serious issue.
But yeah, I don't think that saying it's not an ultimatum is being totally honest with yourself. At the very least, it's an open-ended ultimatum - one without a specific deadline. (Ultimatum: A statement, especially in diplomatic negotiations, that expresses or implies the threat of serious penalties if the terms are not accepted.)
Still, it's a powerful statement and I don't regret saying it to my W.
