Ah sorry, slightly misinterpreted, my understanding was that without slack you cannot stabilize queue sizes which makes OP incorrect(?)

Yeah, more efficient nodes can delay that effect, but it seems that in real world system the existence of buffers means that consequences are delayed in ways that have significance (across careers, elections, etc) and those factors tend to dominate.

yw, nice that anyone reads it, without that i'd just be another mad shouty bloke on the internet, maybe i still am :)