I have been using drift alignment for about 12 months now and after taking time to get the images straight in my imagination, I decided to craft a visual aid and a few videos to explain how I visualise it, using arcs of stars and arcs of telescopes. I'll add the links in the order they should be viewed. The first video here https://www.youtube....h?v=EcVjBptK2ng is where all the hard work is done in the explanation. Please note there are caveats to this video - I use directions and adjustment that are specific to the Southern Hemisphere.
The next three videos are companion videos. The first of these https://www.youtube....h?v=3YoasFk7NEg shows only the adjustments needed to the RA axis to correct altitude and azimuth error for residents of the Southern Hemisphere.
The next companion video https://www.youtube....h?v=16n7n64b5uk shows only the adjustments necessary to correct altitude and azimuth errors for residents of the Northern Hemisphere.
The last companion video https://www.youtube....h?v=-AiHk1BQEVE is doing a drift alignment in the field to bring some of the things explained in the first three videos into practice. I also introduce the use of a smartphone running an app that can produce live view star trails to speed up detecting drift. The smartphone is mounted to the eyepiece to create an afocal image. Once polar alignment is acheived you might then use the smartphone to do imaging or replace it with another camera...
I think these videos provide a very easy and intuitive explanation of drift alignment. You need a bit over 30 minutes to view then all. I hope they help someone.