Hi, there CinqAns. I’ve had the same thought regarding Perlman. It’s amazing what those large fingers can pull out of the instrument. And then you have folks like Django Reinhardt who manage to overcome greater challenges…
My advice would be to practice ascending/descending trills over major scales with a metronome. Work up in speed as you go, but don’t move on to a faster tempo until you are playing crisply. You should be able to clearly hear each individual note you are playing during these exercises. Alternatively, you can pick a tricky lick in a song you are learing (or already know) and play that with a metronome at a comfortable speed…then increase your speed.
You should see some improvements as you keep with it. I would recommend practicing several times a week for at least 1/2 hour to get that muscle memory going.
Finally, make sure that your fundamentals on both your right hand and left are good…have you checked out the basic left and right hand technique tutorials available here on the site?
Keep us posted!! And best of luck!