Lenin - did you ever manage to find a sensory integration OT? (it was you I had a chat with ages ago about that, wasn't it?)
I ahev alsways had it explained ot me that motor skills go thus eg: newborn, with reflexes -> refines down to swiping -> bit more refinement to grabbing -> controlled grabbing -> narrow that down to pincer grip -> fine work with fingers. always form big to small.
so, when we were concerned about dd1's lack of pencil grip etc, despite ggod-ish gross motor skills, ok-ish fine motor skills (liek threading, sorting, puzzles etc), we were told we needed ot go abck over all her gross motor skills, as there were undoubtedly bits she had missed out, and if she couldn't do the big stuff, she wouldn't ever do the small stuff in entirety.
so, lots of swinging arms, dancing and prancing about like something off X factor
- big sweeping movements form the shoulder. then working on gettig it smaller and neater form there.
SI OT helped a lto with some of this, as dd1 also has all sorts of midline issues.
just a thoguht that occurred while reading through - as while it is clear oyur ds has fantastic fine motor skills in one area, they aren't (or don't seem to be) translating across.
some of the stuff on behavioural optometry might be interesting too.