Back in the 70s when I spent 6 weeks in the Marconi Drawing Office School, I think we were taught 3rd angle. These days, I use BOFP standards, which for me generally means a rough isometric sketch (and I mean rough) with dimensions. If I want better, I usually go to F360 at that point. BOFP sketches don't file very well - tend to be single-use only, but fine for the one-off smaller job. I probably do do the odd "projection" drawing, but I have to admit that I can't now remember which is 1st and which is 3rd...