This is an interesting thread...I have no DC yet, but I've read with interest to compare to my experiences at school in the 80s. I was 'encouraged' to switch to my RH by DM, (she denies this now)
but school were fine with it.
I didn't have any particular support that I remember, but my technique obviously did improve at school as early examples show awful smudging, that get better and technique has been fine since about the age of 7-8ish. I dont 'hook' , I'm a paper turner. I think I worked this out on my own and I don't remember any particular support.
Interesting point about whiteboards. I don't feel entirely natural writing on a whiteboard and it is a bit of an effort, however, I can write in a straight line with out smudging. I put this down to the fact I also paint and have developed wrist strength so I don't need to rest my hand on the board.
I use a mouse right handed and right handed scissors. I think that was just adapting to what was available. I don't bother swapping my mouse at home, because I just thought if I get used to it LHed, it'll be difficult to use other PCs. I think you have to bear in mind that realistically, ZERO support will be available in the workplace, so maybe better not to rely on it. I'm thinking of things like hotdesking for instance, where it will be a performance to move the mouse and change the settings every time you move.
Interesting fact - I've just finished a degree course. In my co-hort, LHers were massively over-represented, to about 50%. And it was a science course. Make of that what you will. :)