Let's look at the darling of the "let them cook in the AHL crowd" which is the Detroit RW of the 80ies-90ies and early 2k.
Yzerman - did not play a single game in the AHL
Fedorov - did not play a single game i the AHL, played one season in Europe
Lidstrom - did not play a single game in the AHL, spent two seasons in Europe
Gallant - spent two season in the AHL but was a 6th round pick
Kozlov - spent half a season in the AHL and 1 years and a half in Europe
Shawn Burr - played 10 games in the AHL
Holmstrom - played 6 games in the AHL and spent two seasons in Europe
McCarty - spent 1 season in the AHL
Chiasson - spent 23 games in the AHL
Probert (a "goon" who could play drafted in the 3rd round) - spent 39 games in the AHL
Datsyuk - did not play in the AHL, spent two years in Europe
Martin Lapointe - played 75 games in the AHL over the span of 3 years (went back and forth)
Primeau - played half a season in the AHL
Klima - did not play in the AHL
Konstantinov - did not play in the AHL, spent two years in Europe
Zetterberg - did not play in the AHL, spent 3 years in Europe
If we want to be honest the Wings barely used the AHL. It was rare for one of their
good young players to spend an entire year in the AHL. They would most of the time spend half a season in the AHL and then half in the NHL. They always tested their good kids a few games in the NHL pretty much every years (between 10 and 40).
Their European prospects spent between 1 and 2 years in Europe before coming over but that was probably more a product of the time than a strategy. A lot of their European players were late picks often in the 4th rounds and lower. Fedorov was 4th round, Lidstrom 3rd round, Datsyuk 6th round, Zetterberg 7th round, Konstantinov 11th round, ... Europe was pretty much a black box back then.
If we were the Red Wings of the 90ies Roy would likely play between 10 and 20 games in the NHL this season to test him. And according to many people on this board that would destroy his career