Some tooltips don't give you all the information. It took someone getting angry with me in a regular duty to make me look up a guide that showed that Wheeling Thrust and Fang and Claw became combo actions at level 64, because it's not in the tooltips - you need to also read the role traits to get that information. Because I was playing on a controller and had those two combos on separate bars that I switched between, I never saw the opposite button light up and so I was dropping tonnes of DPS without ever knowing it. So if it wasn't for someone being incredibly rude to me in party chat, I probably never would have figured it out.