Ouch.
David, for that small bench, if I pull that hard the bench would tip over. I have more substantial mounting for my larger vise on a larger heavier bench that I use for hard pulling and whacking. The vises and grinder are mounted to the plywood bases with T-nuts.
They've always been mounted with bolts on that bench, but because it is small, I've found that I sometimes need to move them around for different requirements.
I'd be interested to see the set-up you described. I'm not picturing it in my imagination.