I think the problem is that there's no clear and obvious place to do it anymore ... ie. there's no more Chardok (thankfully). As you pointed out, killing 25 mobs at once can still net a group a lot of XP, but there are issues:
- you have to find somewhere that's out of the way (if your pulls mess with other people you will get in trouble for zone disruption)
- wherever you go has to let you control your number of mobs (no more just running through the zone grabbing everything: if you pull even 30 mobs by accident then that's 5 mobs beating on your group which aren't being stunned by your Enchanter, and that won't end well)
- you have to avoid problematic mobs (eg. ones that snare your puller)
I would imagine there are places that match the above criteria out there: after all, on live people AoEd plenty of non-Chardok places (eg. a friend of mine did late night Sebilis AoE groups during the Kunark era) ... but finding them would require some exploration and experimentation, which means bringing your own group. Also the rewards of doing all that aren't all that great compared to a standard group (as great as it is to kill 25 mobs at once, there's huge downtime in-between) ... so mainly it just seems to me like a good idea if you and your IRL friends happen to be a Cleric, Enchanter, puller, and three Druids/Wizards, and are looking for a fun and different way to level up.