i see from the site you shared that this is a technique that originated from NLP (Neuro-linguistic programming).

*This technique originated from NLP and was often called the Visual/Kinaesthetic Dissociation technique, the term 'Rewind Technique' being originally coined by Dr David Muss.

i did something like this with my first T. she was certified in NLP therapy and would try some of the NLP techniques with me in my sessions. at the time i was a bit skeptical of NLP because the research i had done into it indicated that there was little evidence of its effectiveness. and quite honestly, i never found any of the techniques she used with me overly helpful, especially for reducing truama symptoms like calming my dysregulation or desensitising intrusive thoughts about my truama. like you, i also disassociate and when i started therapy with her i had no idea, and neither did she, that i was DID.