it is physically impossible for Snoke to have kickstarted the entire dyad because according to Kylo, the effort of such projection would kill
Are you referring to when he tells Rey the effort would kill her? In the theater when Snoke revealed he did it, and when Luke later died, my assumption (and I’m sure the writer’s intent given the Dyad didn’t exist yet) was simply that projecting your image into reality for all to see is far more of a strain than a mental link between two people created by a third person. Snoke was using triple the “processing power” for his feat that Luke was, having not only his own mind at his disposal but also Kylo’s (because he’s been in his head for years) and Rey’s (possibly because Rey and Kylo were in each other’s heads in TFA).
The problem is that you have to rely on assumptions in order to come up with all of that. IMO, removing that one line fixes so many problems. Snoke only admits to “stoking Ren’s conflicted soul” and knowing that he would somehow eventually get in contact with Rey so she would come to him. This way, the audience doesn’t wonder how Snoke was powerful enough to pull off such a feat, and they also don’t later become confused by Palpatine’s surprise regarding the dyad. The only thing the audience is wondering is how Kylo and Rey are able to communicate across the galaxy, which would be explained in the next film.
Of course this isn’t a TLJ edit thread so I probably shouldn’t even be sharing this. However, it is still really tied up with this movie so I feel it is necessary.