RE: MOT rating and de-rating for power and current

As far as the corona problem in MOT:

Couldn't we build a huge stack of MOT with secondary windings in series and
plunk them all in air-tight cylinder filled with dielectric oil, then pull a
medium-hard vacuum on the cylinder?  (repeating vacuum as necessary to
eliminate all transient gasses from inside the winding and also to
[hopefully] surround all the copper with a little of the oil?)