1938TS UNDMs; What were they like to operate?

Yes, you're quite right; I forgot to specify that!

The UNDMs were introduced in 1952 with the intention of enabling an uncoupled 3-car unit to stable whilst the 4-car unit remained in service off-peak, but avoiding the cost of a full cab in the middle of trains which took up passenger space. However, off-peak uncoupling was abandoned on these lines around 1960, so UNDM shunting would only then have been an occasional requirement within depots. Perhaps it was even preferred to drive the 4-car unit onto or off the 3-car. I know that vision was very poor. So they would have seen little use. On withdrawal, sufficient shunting cabinets were obtained for the new 1972 mark I trains, so they would have seen further limited use within depots. The 1972 mark II had new shunting cabinets, and the mark I were re-equipped as part of their refurbishment.

What was it like driving from the uncoupling end?

No - UNDM means Uncoupling Non Driving Motor.

In Piers Connors' "1938 stock", on page 66 there is a close up photo of the control panel, a photo showing the wiring involved and a UNDM coupled up to a 'normal'end car.

Unlike S Stock, Victoria 2009 Stock have uncoupling equipment and emergency shunting controls in the middle.

Can only speak for my area, however operating staff are trained on the shunting cabinets, but it’s a cursory “here’s what each button does” rather than a proper familiarisation with the chance to practice in anger. As such I’d say such staff aren’t really equipped with the familiarity to use them.

Splitting trains at one unders is pretty unheard of now, I’ve not heard of it happening on my line in my time. Really there’s little to no need for it. Perhaps more of an issue on the sub-surface lines, but splitting an S stock is unfeasible anyway.

There isn’t much point in training people on something that they will never do in anger and probably never need to. Even coupling trains is very much off the agenda nowadays, which is something I’d say is more of an issue (having personally had to do about 8 couple-ups in the last couple of years - it’s funny now being familiar with doing something leads to more being asked to do it!).

It was the need to split trains to deal with incidents along the line that led to the Operating Department objecting to proposals for articulated cars in what became the 1973TS, although engineers constructed a demonstration pair out of two standard stock driving motor cars which remained for some years. Funny then that 50 years later the replacements for those trains will be fully articulated 9-car sets.

Of course, there wouldn't have much space left with a couple of standard stock back to back, with the equipment compartments! Sorry! photo here

Quite a bit shortened it would seem - two of the rear three windows and the single leaf door!

Getting back onto the UNDM; the 1949 batch was delivered with beamless shoegear like the R stock and like the R stock it was not a success being replaced with conventional shoe beams in the early 60s I think.

Did the 1938 conversions also have beamless shoegear or was it just the 1949 new builds?

I seem to remember something about a cabinet where a control unit could be plugged in by technical staff.

As far as I recall, uncoupling of S stock was not a design option progressed in any way at all.
A plug in controller would just be the tip of that iceberg. You'd need a shunter / T/Op operable uncoupling/coupling system including for the gangway connection, significant control and safety circuit changes and something to stop the operator falling out.

I would hope that there was a solution for this designed in from the start. Wheeled car stands is my first thought.