Something I've been curious about and haven't seen anything asked about it before, if the last FW buff is about to drop off and you have 3/4 combo points and know you aren't going to get another HAT proc before it drops is it worth using a non 5point eviscerate? So far I have been as surely a 3/4 evis with FW is better than even a 5point evis without it but not entirely sure if there's something I'm missing? Cheers.
Short answer: Yes.
Long but not so long answer: The actual best option is to plan ahead and have the CP missing inside FW, it's not like MoP when you could get random FWs from the set bonus, you know exactly when you'll have FW and when you won't. Sub is about managing things, both your CPs and energy are completely stable flows.
Edit: Rupture MS mechanic fucks the previsible flow, but still...
Well yes but surely there's no guarantee you're gonna get a perfect multiple of 5 combo points throughout the FW uptimes? Primarily thinking of the 50 odd seconds uptime at the pull, surely at times having a few left over is innevitable?