A few issues with Archon and the stuck handler:
Clean DB Beta, clean trinity from SVN (though these are all valid from .42-55), clean Adventurer.
1) Archon Strike attempts to cast too fast. Whenever Archon Strike is chosen as the best power to go forward with, it simply stutters the bot around in place, as if it's attempting to cast too fast. Archon Strike never comes out, and it instead just stands there locked in the animation. This is true if Disintegration Wave is disabled, or if the code changed to only allow for Archon Strike.
2) Disintegration Wave is often cast on/off in bursts. I'm not sure if this is due to Archon Blast coming off of cooldown so it is selected as the best power, but it staggers casts of Disintegration Wave. Unsure if that actually influences DPS, though.
3) Archon teleports on top of the monster, usually the Rift Guardian, and stutters in animation like #1. It won't teleport, it won't cast Disintegration Wave, it won't even cast Archon Blast. It stands and stutters as if it's trying to cast a spell but interrupting it with another spell cast.
4) Often, usually in maps like Act 3 barracks or places with sharp 90 degree corners, if the player moves along the corner and there is a mob, it will cease all actions until the mob is either dead from AoE or moves for the player to move through, or the player dies. I assume this is the stuck handler not kicking in, which is on the bug tracker already.
I'll take a look at the code more in-depth whenever possible, I work in the field so I should be able to offer more valuable input for helping you see what's up.