I was watching a video about a review of the Paramount MYT and they mentioned the T-Point mount modelling in the SkyX which improves tracking accuracy. In essence you select a couple hundred stars for it to model and it improves tracking and goto accuracy, so that you can image, unguided for up to 5 mins. I was wondering if the Mount Model tool in Ekos performs a similar function.
Would it also require a mount with absolute encoders or will any decent mount do?
So that really depends upon your mount. I have the Losmandy Gemini Mount and it can take a very large number of alignment points. The INDI EqMod Driver can do a similar number of points, but it does it in the INDI driver software instead. A number of mounts can only accept 2 or 3 alignment points, but if you have one like the first two I mentioned, then yes, you can do the same thing the TPoint modeling does. The Mount Modeling tool in Ekos is really just an automated way to do a whole lot of alignment points in an automated fashion. If your mount can take advantage of it, it will work great. But if your mount can't accept more than a couple of points, then it wouldn't help.