As long as you keep your dungeon runs to 6 minutes or longer, using ooze won't matter. I'll run ooze with no speed boost items or speed boost items with no ooze to generally keep my dungeon runs to 6 minutes. Also this doesn't account for queue times. I RARELY ever get instant queues even with a full group and often those queues will be around 60-120 seconds (1-2 minutes) which can be applied to your 6 minute timeout. So a 4 minute run with a 2 minute queue after keeps you at the 6 minute cap for dungeon timeouts. But again, those queues will likely be unpredictable so I've found a dungeon time around 5 minutes + queue times to have very little chance of getting under 6 minutes for the dungeon timeout. Like if I get a fast queue one run, I often will make up for it after a following run with a longer queue. A good addon to keep track of your dungeon times is Nova Instance Tracker. Also I find it's probably a good idea in general to get used to not using ooze because eventually that shit is gonna get nerfed.Oh and keep in mind that a customer wont like hitting instance cap despite it actually being the most efficient way to do dungeon. With that said a BiS toon using an ooze may end up making you less money in the long run.
This is why I didn't mention it in https://xpoff.com/threads/retail-power-level-tier-list.98933/#post-1306380it's probably a good idea in general to get used to not using ooze because eventually that shit is gonna get nerfed.