With all due respect to his efforts, I feel that is an excessive amount of fan service.
The whole concept of intercutting RotS and the Siege of Mandalore is already a lot of fanservice.
I can understand that point of view.
However, I deleted a handful of scenes that I’d felt were slowing down the story of ROTS; without the SoM scenes, it would only be an hour and a half.
EDIT:
For me, this fan edit isn’t really fan service as much as it is showing a more complete story, where each half of the story informs the other, especially in the scene where Ahsoka does some quick research on Fives that uncovers the mystery behind Order 66.