The way you present peenix like your personal holy grail all the time implicates that you should better go back to feenix in order to be satisfied.
It's just crazy how you engage in every thread on this website and yet you never contribute with anything remotely productive unless its directly benefits you (your "work" on boss resistances). I know you aren't dumb, so it kinda baffles me how you always manage to spout ridiculous crap. The discussion about Feenix Naxxramas is super relevant, and some research on boss-numbers, kill-times, what sort of guilds could kill what bosses etc. should be done by Kronos Developers. Sarei brings an important perspective that is super relevant for this discussion: How medium - or lesser skilled - guilds do in Naxxramas 40 when encounters have altered HP and damage, cause in reality, that's all we are discussing; if this server only had VG/Synced/Onslaught-quality guilds, then buffing HP/damage would be an easy decision, as that decision would have almost zero backlash (these guilds would eventually clear it and probably wouldn't even whine if it was too hard, as most of them most likely welcome an actual challenge). However, on Kronos, there are several medium-tier guilds which could run into trouble if the bosses get too hard, and while Naxxramas shouldn't be catered towards the "casuals", you simply can't ignore this segment of players completely either as they are detrimental to the longevity of the server.
For instance, here's what I would think is a valuable contribution to this discussion: Kel'Thuzad was never killed by any guild on Feenix without worldbuffs, and as far as I know, he was introduced at a later stage where people were already decked in T3 (someone correct me if im wrong here). He had 300% boosted hp (dunno about damage) so about 9 million. If he was unkillable on Feenix (or atleast very, very difficult even in T3) without worldbuffs, then trippling the value is most likely too much on Kronos should wbuffs get disabled.
If Sarei's medium-tier guild did decent (10 bosses over the span of 3 weeks?), with average buffed values of about 80%, then that tells me the lesser guilds on Kronos won't be stuck on Anub forever with the discussed values (25-50% hp). If the top guilds on Feenix couldn't kill KT at 300% without worldbuffs, then it tells me the medium-tier guilds will never be able to do it without worldbuffs.
Feenix and Kronos may not be totally identical, but there are valuable lessons to be learned from some of the information available when trying find the sweet spot between unkillable and difficult by altering values.
EDIT: Lmao, you are literally one of the people who bring up the fact that lesser guilds may struggle if content gets buffed, and then when one of the representatives of this segment tells a story about how his medium tier guild did in Naxxramas with buffed values, you tell him to go back to his "holy grail of a server". I'm having a hard time here Chainsaw... Really?