Except Grabovski isn't Clarkson... And I am worried about Nylander, but Shanahan has come in now and has started putting in place the necessary tools to improve the Leafs' player development record (which to date is pretty terrible).
There was a good chunk of risk placed in drafting Nylander, and it's far too early to say he's made it or busted, but I think if it weren't for Shanahan and his organizational changes, the Leafs wouldn't have the same hope to see him develop properly, and the same applies to Seguin.
What you're saying with your post is that player development under Burke, Nonis, and Shanahan are all the same. I strongly disagree. I mean, just the introduction of the Analytics Department alone will have major ramifications on player development in Toronto. They'll be implementing high-res movement tracking to gauge strengths and weaknesses in muscular strength, agility, dexterity, etc. on a scale unparalleled by "conventional" eye-test systems.
That will in-turn result in better training regimens for each player tailored to their specific needs and abilities.
And it's just one facet that Shanahan has the Leafs investing into that Burke/Nonis never thought to try, or opposed based on their ideological beliefs.