Personally I prefer the slip on brass ferrules rather than the screwed as they are generally a thinner wall e.g. 1mm as opposed to 2mm. If I ever get short then I’ll normally buy some brass tube that is a 1mm wall thickness and cut my own.
The video just gives you a quick insight as to what I do without a lathe and after fitting you can shave a little off the thickness with the correct papers if you want to go that bit extra.
Obviously if you have a lathe then this would be easy to do but the video is aimed at the people who don’t just to show them there is potentially another way.