Well snow gets in the boot for one. I found that out. I did ski that exact type of snow. Cut up wind packed mounded powder.
What you talk about is something that's always bugged me about boots for me. Too much space in the upper cuff. Then tighten and it's too locked. Or, the cuff wants to pull my shin out of the position that it works well in (current boot).
I sort of stumbled on this work around btw. Part of it stems from another boot where I skied the Vallée Blanche with the top buckle undone because I just couldn't take feeling like I couldn't get over the front of the boot. Not enough for lean for me.
This may be an area where a lace up liner has advantages because it holds together as a unit. But if you have a snug liner, the bottoms are buckled, and a booster it may not be that much different really.
I don't consider this a great solution btw, but it's better than a locked up leg. Essentially I'm experimenting. It may actually be safer than overly restricted. The Fischer has a wire clip that holds the bale in the groove which is nice. Never thought I'd care about that.
I found to ski that snow you really have to tell the skis what to do, be very intentional with lower leg movements. Knees going into the hill/inside the turn. Generally I only think knee movements like that in soft snow. For years knee movement was "bad" and I've had 2 acl's and a meniscus. So I've not thought knee movement. But, that's probably overblown.
Anyway, active functional tension in the legs. Shopping for turns is going to kill the whole thing.
Telling the ski what to do means you're throwing it on edge, lower legs/knees go in. (Angulation) The ski is now banked. Because the snow is softish, it's going to create a platform, bend and go in an arc. While it's doing this you are looking where the next turn path is and moving into the next turn. It's very active, not la di da,
A wide ski may be more difficult in some ways because there's more force back to move your boot. You might try narrower skis first.
The connundrum is steeper terrain and certain snow conditions put more force back. So cuff looseness can lead to a floppy ski. Which isn't good. But try to minimize the bad and increase the good. Getting early angles the ski now has a direction and purpose. Essentially you're doing a lot of work to ride the ski for a brief second and on to the next.
It also helps your feet warm up and acclimate to the boot to do a first run with loose boots.
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