[AndyFurniss]

This looks to be quite a mixed sample - unless ffprobe is misleading me or I misuse it there are a lot of places where the telecine/pulldown pattern reverts to normal interlaced.

Thinking as I type I don't know how you would ever (currently on a computer) get this perfectly smooth.

Of course telecine is not by design smooth - it was invented for 60Hz (/1.001) displays to play 24Hz using repeated fields. If the sample were pure soft pulldown the decoder/player could easily output 24HZ - but it isn't so that's not an option it needs sometimes to output 60Hz.

I live in pal land, so I don't really know how disconcerting 3:2 looked on an analogue TV - or a modern TV.

Given that modern TVs don't really work at 50/60Hz anymore it's quite possible that they handle this OK (or better) with frame interpolation/smoothing. Modern TVs often boast of internal processing at really high Hz rates.

Edit: forgot to put that I am not trying to say there is no issue for you that couldn't be handled better by player and or deinterlacer.