I sort of disagree. I think in years past the Shield was an excellent breeding ground for test cricket. The obsession with youth has seen some high quality first class cricketers moved on before their time - I think players such as Maddinson would learn more playing with Katich in the top order than Tim Cruickshank, for example.
It's happened at grade level as well, young players have gotten comfortable passages through each level because of their involvement in the NSW cricket system - Look at Mitchell Starc, did bugger all in grade cricket to warrant a first class debut, did bugger all in first class cricket to warrant a test debut, has done f**k all in test cricket and people want him starting at Trent Bridge.
So I think the biggest issue is that we've lost the balance at first grade and first class level, and thus are not progressing on an international stage. I agree that Hughes, Khawaja didnt get treated well in their initial runs, but neither have they earnt their spots back since, and I think that is telling. Khawaja still hasnt shown improvement in key areas - game awareness, looking to tick the strike over and not get bogged down, whilst Hughes still struggles with top class bowling. The only one that's been dropped in recent times and has truely gone back and improved their game is Steve Smith.
The Ashes isnt about player development, it's about winning, which is why Rogers has been chosen. To go with that he's done far more than the other options to earn his position.