I see nothing wrong with you thought processes, but I think unless there are circumscribing conditions CIG 0 RVR-3 and you require a long flight to the alternate [require a TO alternate] I may stop a little past 80 up to 100--or you're on a contaminated RWY--I'd GO---what ever entails the lesser risk at the time in your judgment--bases on outside factors and circumscribing conditions--not clear cut answer--but you'd then be the commander---and as with all PICs--you'll have the final authority, but then they'll blame YOU for anything that goes wrong ---that's the responsibility
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PA