Coming from a guild who has cleared Kara and is continuing to clear Kara we find the buff, short sighted, poorly implemented and over-all a completely disastrous idea.
Firstly the buff. It's a 50% buff to the damage that trash mobs do. Not bosses, trash mobs. This means that the shades on the stairs leading to Curator hit for 12-16k on full Kara geared tanks - RiP paladin. This is a two shot on some of the best geared tanks on the server - at best.
This is completely impossible for any new guilds to clear Kara in a reasonable time-frame. Our guild is well geared, mostly Kara epics and some from Gruuls lair, and yet we still spend 3 hours getting to the back entrance. Why, because the trash occasionally just one shots your tanks with nothing you can do about it. If a dps pulls agro, they die instantly to a 10k non-crit. For reference, our dps warrior tanked Atumen the horseman for about 2 swings without dying. That's right the first boss hits less hard than the waiters outside Moroes.
This means that no guild is progressing through Kara at a reasonable pace. It took Panacea which most consider one of, if not, the best horde guild 1 and a half hours to get to Maiden. It took us a similar length of time, a new guild, i'd be surprised honestly if they can get to Attumen in all honesty. It also means that getting to Curator comes with a 100g repair bill price tag for any plate user.
A completely short-sighted change. That the time should instead be focused on scripting drop rates correctly and fixing bosses with broken mechanics. E.G curator who's adds don't drop the pools.