He used to do that with Pecco (And the other academy riders) long before Marquez joined Ducati- ie Racecraft advice. As I remember, the advice to Pecco usually is to not choose the wrong ....... tyre which according to Rossi, is something he did a lot.Rossi deserves great credit for the academy and the renaissance of Italian riders in the sport, Bagnaia being the most successful so far and one who has succeeded greatly, rand I for one am very happy to give it to him.
Boasting publicly about advising Pecco on how to deal with MM not so much, given it pre-supposes two things, firstly that Valentino has or ever had any expertise in how to deal with MM, and secondly that MM did something dastardly to Rossi, neither of which I consider to be true.