I am not sure i understand the approach with differentials and high astigmatism.
I saw jake’s video regarding the topic
So there, he suggests a rule of thumb of subtracting 1.5D from full prescription and add -0.25 SPH for every -0.5 CYL you reduce, generally start with swapping 1 cyl with 0.5 sph
Then there is this:
Which says to deal with astigmatism first for close up and only after eliminating it start reducing it for distance (not to mention equalizing astigmatism - if i get rid of it for closeup, but leave it for distance, i will have a different L/R ratio on different glasses, and that is not recommended, according to my understanding.)
So if someone can outline the recommended strategy for dealing with high astigmatism and close up, please share your experience and advice, and let us have a discussion to clarify this area a bit.