Congrats on dredging up something that is far older than even my current pbn screen name...
Also, you happen to be wrong.
Evil recomends a HP tank for the omen, as the recharge we are speaking of is the REGULATOR RECHARGE. The det needs this pressure (800 or so) to keep up with the gun at high rate of fire.
The valve can recharge far faster than the det can on the omen, and thus a high INPUT pressure is necessary to keep the detonator from suffocating.