Sometimes you just need a little kick. I had always feared to bring a soldering iron near white metal - it just seemed counter-intuitive as it melts so easily. I guess having soldered electronics for around 50 years I already had some basic skills, just never on white metal. Once you showed me and I tried it, it just fell into place.
It's amazing what can be taught in a few minutes. You made a point about solder also being the 'filler'. Didn't mean much at the time, and against what I'd learned in electrical soldering, but, it's that that enabled me to make a slightly rough K's casting into something sort of resembling a model. There was a fair bit of solder filling (and filing) needed around the smokebox and front buffer-beam, but by using solder instead of plastic filler I could do that in minutes rather than days, and the results are far better.
It's not just about teaching techniques and skills though - it's about inspiration and encouragement to get on and do stuff. You have to try, and sometimes fail and then figure how to fix things. I quickly learned is that the side of the soldering bit is just as hot as the tip and one careless touch will melt something. Only happened once though.
As someone on the cusp of retirement (probably within the next 6 months or so) the thing I fear most is getting into an "I've got plenty of time, I'll do it tomorrow" mode. I completely agree we need to find reasons to do stuff - that's not always easy, but sometimes a little encouragement and inspiration go a long way.
I have an Albion Models M.S.W.J.R. 4-4-0 waiting in the wings once I finish the 97xx pannier.
Nick