As someone who has been in a 3 Hour 2.0 Mod, and witnessed 3 different full 10 minute meditations in that mod (Love you SoMi!); there is absolutely no reason why quicken meditation can't be used while in combat. Virtually every other aspect of the game is tied to the honor system and inherently relies on players to be honest and update their own battle board with virtually no oversight. To that end, Quicken Meditation isn't the concern. As it simply allows you to follow all the same rules of meditation but at 3 seconds. All of the other uses of meditation, are honor system. The interaction however is a 3 second meditation to spend available high magic; particularly into Higher Manifestation & Cloak. The concern is that spending High Magic (quickened or not) is done with a Marshal. So while Quickened High Magic is a possibility with the rules, it faces OOC limitations which should be respected. Likely this is going to be a "how your game handles it" because short of ritual casting, I personally have not yet been to a game where I wasn't able to "grab a marshal for a quick question" Especially on a big mod - where there is usually at least 1 marshal to simply oversee the chaos. that is also not including your ability to grab a marshal while their NPC/crunchy is on its respawn timer. I think in all, Quicken Meditation + High Mmagic is completely possible and follows the rules as written, however requires some patience on behalf of the player using it. As quicken Meditation doesn't remove the need of a Marshal for High Magic use.