As others have said, its very rare I flash anyone. My preferred method if I want to let someone out/across is to just take my foot off and allow a gap to open up, if I notice too late and would need to brake then I just don’t. Occasionally I will point to make it clear who am I waiting for but only after looking to see whats coming up behind/around me.
This morning I raised a finger off the wheel at a colleague driving the other way, next thing I know a pedestrian about 50 metres up the road has stepped out, it wasn’t until they were halfway across and said thanks to me that I realised they thought I had invited them across! No matter as I was doing 20mph and a fair way back but still…
totally ignoring the fact the van was pulling a large trailer
I get this…my trailer is huge and white and very heavy, its always a difficult decision to go when invited as it takes a long time to get moving (and even longer if I want the horses to stay upright) and its rare that the ‘flasher’ has taken this into account. I can’t really get going out of 1st until its all in a vaguely straight line. Another is slip roads joining the motorway, it can be quite scary when you know the joiner hasn’t checked their blind spot and is trying to merge directly behind the van whilst I try to eek out another 2mph to pull the trailer into their view.