I'd be fine with that if you could find a way to work well. The only problem is, how do we determine when they're hurt enough to be saved by the bell and when they're not? Is the ref supposed to determine it and let them know? And if so, now the fighters have to look out for a symbol from the ref at the end of the round to see if they need to continue or not.
I think the idea is good but the implementation makes it better to just leave it the way it is.