Yesterday I did a test with MRA 4.3.4 on my IPhone 11, using track navigation with Automatic recalculations switched off.
I must say that in general this is a big improvement.
Deviating from the track went well (even though it would have been nice if together with the "Ga terug naar de route" text indication on the screen there would have also have been a one-time audible notification), returning on the track also went smooth.
But: Further down on the same track it appeared that MRA still had done some recalculation of the route, with the blue line taking another direction than the white line. When I decided to follow the original track, i.e. the white line, MRA behaved as if I had deviated from the track, see the below picture.
@KeesV Happy to read it was a positive experience.
Could you perhaps share the route you were driving, indicate where you left the route and where you rejoined? That is the minimal information I'd need to determine if it made sense 
There can still be sensible reasons why there was a minor deviation.
@Corjan-Meijerink
Thanks for the quick response!
For privacy reasons I will only share the route directly with you via email if that is OK.
Below is a picture with an overview of the track and a picture showing the locations of where I deviated from the track and where I rejoined.
Kees
Today I navigated the test track again with Automatic recalculations switched off, leaving and re-joining at the same locations.
Also this time MRA recalculated the route.
During the drive I periodically checked if recalculation had taken place by toggling "Toon gehele route".
I discovered that the recalculation happened just after re-joining the track.
Below is a screenshot just after re-joining the track.
I hope this makes it easier to find the cause of the recalculation.
That's interesting, and I'm curious about explaining this effect as I also try to understand what happens when a track re-calculation occurs.
To get it right, what does "by toggling Toon gehele route" mean?
@martinphogel-de Google translate says (Show entire route)
Indeed, it's by using the following key:
Thank you! 
Of course, I could have looked that up myself... I was probably busy thinking about the actual question of how to see detours travelled afterwards. By comparing the track log with the track, right?
@KeesV did you share the route with Corjan. If not I’m willing to help if you share the route with me in a dm
Honda Goldwing GL1500,
Honda Silverwing GL 650
DMD2 T865X 8 inch Android tablet using MRA next for navigation
Garmin XT (almost in the cupboard)
Samsung S20FE mounted on a Quadlock and using Android Auto in my car
@Marinus-van-Deudekom
I shared the track with Corjan by email.
Yesterday I navigated the test track again, using MRA version 4.3.6.
The same recalculation happened just after re-joining the track.
@Corjan-Meijerink
Have you found the cause of this problem?
@KeesV Happy to read it was a positive experience.
Could you perhaps share the route you were driving, indicate where you left the route and where you rejoined? That is the minimal information I'd need to determine if it made sense
There can still be sensible reasons why there was a minor deviation.
