Regarding technique under pressure - its more of a mental state than technical. Your underlying technique is solid and getting better with more training. What you need to make sure is that you learn to let the technique dictate the flow of the race not let the running dictate the race pace.
At big races I would say getting your head in the right place before and during your race is the most important aspect to doing well. You have usually done all the physical and technical stuff beforehand, and then the mental stuff changes how you use that on the day.
So I agree with Jon, I don't think the solution here is more technical training. Your technique is good, better than 10mins mistakes on a tio leg for sure, and if you keep doing what you do it will stay that way.
Before the next big race (jukola?) try to read up on a bit of sports psychology, and see if anything rings true with you and you think can help. Then try it out.
Would be great to see you smash jukola!