Sadrik said:
1. Ah so you use solicit psi crystal to maintain the control body! Line of sight doesnt the psi crystal see you if he is hanging onto your belt? or anywhere on your body really (I suppose except in something)...
Precisely. But, if the psicrystal can see the Psion, then enemies can see the psicrystal. Attacking and damaging the psicrystal can force the psicrystal to make a Concentration roll to maintain the Control Body.
A simple Fireball or Lightning Bolt could force a Concentration check if the Psicrystal misses its save.
Sadrik said:
Actually, it is not a small deal for a well designed Psion.
Defensive Precognition is practically the only powerful way for a Psion to boost saves (and is another way to boost AC), so knowing that it does not work with Control Body is important.
Psions do not have good Fort or Reflex saves, so giving up the only good way to boost saves in order to both fight in combat and manifest at the same time is a balance point.
For example, Blindness is a Fort save. So, if a Psion does the Control Body trick, he is more susceptible to a Cleric's Blindness spell than if he had Def Precog up. The Psion is also susceptible to spells like Darkness (which will drop both the Control Body and the Solicit Psicrystal powers since Line of Sight drops).
Not only that, it is important to note that the AC of Def Precog does not work with Control Body. So, it forces the Psion to have and use different types of AC powers when using Control Body.
So yes, the Control Body trick can work. But, intelligent opponents who figure out what is happening can disrupt it. This is important for a player of a Psion to know.