Quite some time ago, after I'd already done part of the aforementioned research, I decided to carve 'PRO-EXERCISE' on my forehead, in the manner of Charles Manson devotees. I no longer debate this position with ANYONE, concert pianist or otherwise. I try to avoid argument; I seek instruction and advice from those I choose to follow. Here's an example of my kind of guru: concert pianist / teacher Graham Fitch. Please watch this video in particular, if you can spare 18 minutes.Piano masterclass on Technical Exercises
Can I offer some alternative fingerings?
So the question, echo'd here, what is the aim of the exercise you have modified, why are you making a thumb jump exercise?