I found 90 degree lock offs to be pretty useful, on steep terrain especially. I was crap at lock offs, and once I improved them certain moves went from desperate to not a problem.
I did repeaters with a pull up bar - and something like a bungee cord for assistance, until I could do without.
Also, I had to work up to it gradually (dodgy elbows) but when I was at my best on lock off training, outdoor full lock offs were no longer tweaky moves.