This is Weaver-specific, but...
OK. Assume you're right handed, so you're "bladed" a bit with your left side forward. This is a natural stance to go to the Weaver from. We'll also assume a strong-side holster of some sort, you're at condition orange but it's not yet time to draw against that...well let's say "agitated gangbanger type".
Oooops, he's pulled up his sweatshirt and you see a gun at his waistband. NOW it's time to draw.
One option:
Take your left (leading) leg and bring it hard right, across your body while taking a "long step" to the right. Your right leg bends and you drop to that knee, right foot hasn't moved but of course it's now on it's toe.
While that's happening you draw and you're twisting your upper body radically left into a Weaver-ish hold. Your left knee is pointing to your right almost 90 degrees from the direction your gun barrel points.
You've got what I've been privately calling a "Kenpo Weaver" because I've seen this type of crossed-up thing used as a punch taught in a Kenpo class.
It feels really "tight" across the upper body and it's an incredibly stable shooting platform. It's also dropped you some and put you about 1.5 body widths off-line. Almost as cool: since your right thigh has stayed vertical through all this, you don't have anything impeding your draw. All other off-line movement jiggles your holster all over the place, including bending it which impedes the draw.
It has some downsides. Once locked into this position, swinging your gun barrel right is easy but left means rolling onto your back and shooting past your knees...which actually isn't the worst possible idea but it seriously limits mobility. Or, to move from the "Kenpo Weaver" without rolling onto your back first really needs a forward roll...hope you know how to do that...I "can", kinda
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Another question: what does an Isosceles-type shooter do to move laterally?
One option: bring the off-side foot (we'll say left here) back and right, so you "blade" right-forward and shoot one handed "Olympic style" while backing up?