What are you talking about, on groomers or on powder? I think personally steep groomers are more difficult then pow since you have to commit far more to sticking your edge and transitioning then you do in powder,(you also gain more speed).
Initially steep terrain scares you into side-slipping and avoiding your transition because since the pitch is so high; you gain speed far faster then you are used to. This means that you have to be in control as soon as you drop in since too much speed on certain terrain = out of control = crash.
First of all, make sure your edges are maintained and SHARP
. Magnetraction may help with icy patches.
With that said, I actually find the reverse. That is, groomers (or rather, packed because at a certain steepness, it's not groomable I don't think) are easier than powder...at least the powder than has been ridden on before. I don't have much experience with fresh powder.
The reason why is that powder (if ridden on at least) is more variable and bumpy with unpredictable pack density
(is that a term?). Thus I have found that my board goes all over the place more and I have to constantly adjust for chaotic terrain and tire out my legs. I don't know when I'm actually going to accelerate or decellerate and sometimes even inadvertantly come to a stop....which throws off my rythm.
With more packed terrain, there's less of this problem because what you see is what you get
usually. And although you gain speed downhill a lot faster, it is more controllable. I have no problem with picking up some speed, as long as I know I can slow down at the right moment. However, sometimes you have to realize you cannot stop in a certain area.
One of the key mental aspects for me => Get over the fact that you will have to lean forward... A LOT.
This facing downhill can be nervewracking in steep terrain but if you do it, it will align your neutral body position to the slope
(as if you were on a leveled slope) and allow you to manuever your board MUCH easier. You will also gain speed much easier, but as I've mentioned, at least you will be in control. If you get scared and put your weight on the rear by standing "upright to gravity", it's real difficult to turn and you might crash because you can't control your direction and stop as quickly.