Is this an accurate assessment?

The Lionel service manual indicates this is true-
"While E-units usually control but one motor, it is possible, to control as many as four motors simultaneously by connecting them to a single E-unit in parallel."

Thanks, that little factoid has eliminated my reservations about putting a motor in a dummy engine and paralleling the motors to a single E unit.

Whats the worse that could happen?  ,  You will burn a set of fingers or melt one of the power leads into the E unit

Well, I had concerns that the current draw would cause an arc when the contact drum rotated and made up or broke the connection, leading to burning the contact fingers, and pitting the drum such that it would become intermittent or useless.  Seems Lionel over designed the E unit, or just made the innards the same but arranged it  in different configurations to run 1 to 4 motors, unlike the solid state counterpart, where there are one and two motor capable electronic E units.

When I had my Lionel back in the  70's  I had a few sets of 2333's with the horizontal dual  motors and they went trough fingers on a regular basis,( and drew amperage like a pig.  I wouldnt see vertical dual  motors being nearly as bad as long as they run well and smooth, Like I said running for may just be a matter of maintenance, replacing  fingers more often , I think the mechanical  e  units should do it

When I look at the contacts and drum in an E-Unit, I don't see something that is going to last a long time with high current switching.  While Lionel may have stated you can run four motors with them, I personally wouldn't be first in line to try it.

I agree with GRJ that the drum and wipers look small for amperage they handle, even with one motor.  The use of them to handle two or more motors is questionable.  Amperage is higher with heavy or long trains and frequent use like the E unit F N R cycles even with one motor.

For just running I like to lock the train in forward when I can, to take some of cycles off the E unit.

To run two or more motors on one E unit will probably buy you more wear and tear and repairs on the E unit drum and fingers.

Charlie

Not so sure they are that fragile. I have several post war diesels with twin motors and I have never had an e-unit have problems with the fingers burning, and I wasn't exactly gentle with them.  I wouldn't wire 4 motors on them, but 2 motors it should work okay.