At first, that's EXACTLY what I did. Until it resulted in my archon turning on me after only a couple fights.

Archons don't defend themselves as well as angels do, even though they all have perma-sanctuary. They also don't have the option of chaotic regeneration like angels do. This means archons get beat up much more easily than angels do, and when their hp goes down, so does their morale. When they get down to around gushing blood, their morale has dropped enough that they heal less even when not fighting, they stop communing some things that require a higher morale, and if they stay that low long enough, they'll actually turn on you, even if you're orderly good.

Take a blazing archon for example. When blazing archon morale gets low enough:

As a goodie:
Archon takes longer to enter room after moving
Archon waits until conjurer HP is at a lower % before healing
Archon waits longer to renew preps when they fall.
Rejuvenate drops to heal
No commune of Fly


As a neutral:
Archon takes longer to enter room after moving
Archon waits until conjurer HP is at a lower % before healing
Archon waits longer to renew preps when they fall.
Heal drops to cure critical
No commune of Fly


If you are fighting in a situation where Warp Dimension is possible and useful (i.e. no other non-aggro mobs around to hit with it, and not fighting something that's immune to it like undead), and if you have parry and shield block at 100%, AND if the fight you're in isn't already taxing the archon's ability to keep you healed, then it might not be so bad to have the archon engaged in melee and not healing you. When I'm well prepped and fighting the ice drake, I actually prefer the archon to get engaged, because it makes the drake die much faster, which means less chance of an annoying dragon bite. In that case, though, I also know that I can flee if I have to, since I've usually already dealt with the ice para-elemental by that time.