this is all true but, as you said those who notice quick reving, regardless of how it was done, will assume, mods/hacks, because of this assumption, 1 click rev is a noticeable mod, regardless of if you have the mod or not, but the best way to put it would be, its noticeable if spammed, i evg and pvp and ive never seen anyone with the ability to get up in under 5 secs, those who have, fully admitted they were using 1 click rev, i do agree with with high specs its possible, but your only looking at a handful of people on the server who could do that, consectively. It is my personal opinion, but i do feel if someone asks if a commonly accused mod is noticeable, you might want to go ahead and call it noticeable. Purely for the fact people will assume thats what it is.
Yes, it is possible to get up in under, i think it's 3 seconds, with no mods. Not likely anymore, but i assume still possible for some users.
Before dynamic i evg a lot more, didn't have one click rez either. I'd get killed, hit esc, and be on my feet by the time my char finished the knock back animation. So it looked like i'd just get knocked back and instantly stand up. With the current font lag and UI, idk if it's still possible. Using abyss' bitmap font and one click rez, nowadays if i evg i still only get up at roughly the time my char hits the ground, if i'm spamming esc when i die.
Depends on specs and/or mods, proximity to servers, and try hard i suppose. I just don't really care as much any more.