It's a shame there isnt a road cycling course we could go on, I would sign up in a beat to improve my road cycling, like IAM for motorists.
Well, there are courses but the problem with bikes is that much of what we need to do will be dictated by local circumstances.
In the section in your video, for instance, if it was downhill rather than uphill, then you'd be doing (for example) 25mph rather than 10mph and taking the right lane from the start could be the correct thing to do.
I worked somewhere which had a similar quandary. Coming out of
this junction up a hill and onto a one way ring road, I needed to be in the right hand lane about 300m further up the road. If the road was clear, and as I was coming down a hill to the junction, I knew that I could maintain 20+ up the short hill so I'd go straight into the middle of the right hand lane. If there was anything coming, however, I knew that I could barely break into double figures from a standing start so I'd keep in the left lane until the top of the hill, at which point I'd look to make my move to the right.
Try teaching that in any school, though.