For Steel Cyclone. It's true that otherwise it would still makes sense, although returns are smaller.
If you belive the current theory that you can only DA on the first two hits, let's look at Raging Rush. With Warrior's Charge up, first hit being 100% and 3rd hit 0% regardless, that leaves a 30% chance to turn 4 hits into 5 hits. So a ~30% chance to get a 25% bonus, averaging at ~7.5% bonus damage. And without full DA gear you'd still get at least a 15% DA from trait/merit, and maybe even a bit extra DA on certain WS gear (Ravager's Cuisses +2 and Atheling Mantle come to mind), so you'd still have ~20% even without going for DA itself. So without gearing for DA, you'd get a ~20% chance to get a 25% bonus, meaning still a 5% increase on average. So with Warrior's Charge up, even on a multihit WS, you'd only get ~2.5% extra damage increase with DA gear. And that's thinking optimistically.
It may still be worth it, but can quite possibly be outweighed by good alternative WS gear. Sea gorget instead if Ravager's Gorget would be a good example. This still assumes that only the first two hits of a WS can DA, which I'm still not convinced of, but I believe it currently is the most dominant theory.
Anyway, it doesn't invalidate my point that Warrior's Charge damage on WS outweighs the extra TP gain you would get from it.