I think that is rather biased way of framing the debate.
I never really consider nonlethal damage to weigh heavily on the question of the nature of HP, because I just thought of them as a much needed replacement for vomit-inducing ancient subsystems (dragon subdual and brawling).
At a practical matter, 3e made healing more available for modest cost, because the daily healing rate was increased and it was so easy to have one person in the party dip to gain access to CLW wands.
In terms of play experience, 3e felt somewhere between 1e/2e and 4e/5e. At least to me.
So, naming 3e as the counterbalancing data point to 4e/5e, with 1e/2e implied as near the middle ground seems to undermine your own argument. IMHO.