Understood - mostly want to share in case others get in a similar situation. In general the techniques that I mention work OK - even to the point of being able to support my whole weight comfortably with the brake strand while remaining in control, if necessary. If nothing else they're worth anyone keeping in their back pocket, especially if using equipment at or beyond the limit of their spec...
I also see soo many people not really appreciating the usefulness and importance of the brake hand, and just thinking of the safeguard as "pull to descend" which I find to be concerningly dangerous.
I use my safeguard on a fairly long bridge. This lets me position my brake arm to more easily control a heavy load. I'll load the brake strand (generally with 1 arm wrap plus grip, or possibly a solid wrap around my hand if I plan to let rope out one arm at a time) with all of my weight before descending, to make sure that have the appropriate grip and friction to do so comfortably if needed. I predominantly control the descent on the brake side rather than trying to modulate the handle, and might even fully open the handle. This really limits the chance for a low-friction event (like a wet rope) to catch me by surprise, or for me to screw up if I'm cold, spiking adrenaline, whatever. Before I even touch the lever I already know I can comfortably control the maximum possible force.
