NST vs. MOT ???

Whenever something seems too obvious to me, I have learned to treat the
conclusion with great suspicion. So
here is your chance to completely demolish my reasoning.

I have a 12kv/30ma classic (boat-anchor) NST I have treasured for years as
the source for my HV experiments.
Besides, being heavy and electrically delicate, I am not
sure the classic style NSTs are made anymore. I have
no ready source for additional NSTs.

On the other hand, just driving across town today, I snagged
two discarded uW ovens destined for curbside pickup. Not
only do they have the MOT, but also a HV diode and HV filter cap. (nice
triac too).

I calculate that MOTs can deliver from 140ma to maybe 300ma from a full size
uW oven.

So why can't I take 3 of these MOTs rectified to DC with
their associated salvaged parts, and series them like three 4.5kv batteries
(e.g. geinacher cascade)? Shouldn't I end up with a 12-15kv supply with over
100ma output? All this for FREE and coming in under the weight of my 30ma

Even if dumpster diving isn't your idea of fun, the local Goodwill store has
lots of used working uWs for $10-$20.

Oh, and no TAR in them either!