The significance of youth coaches

Obviously a youth coach's stats will determine how your under 18's or under 20's will do and how much they can improve. But I was wondering if they have any influence into which regens come into your youth squads? Or do your scouts and youth setup determine the quality of the regens every year?

Youth facilities and team reputation are the deciders on the kind of youths you get AFAIK. I know that any club can get any level of player, but I believe the percentage chances of the level depends mainly on the two above (with a floor and ceiling bweing placed on each level obviously).

I have no proof that youth coaches make any difference, but i've found that even with a high rep and the best facilities you can only get rubbish players through for years.

Then suddenly get loads of great one's coming through and often it coincides with appointing a new youth coach, that could be why AI teams pay some of the youth coaches so much money.

I don't think they are really that important. I normally have one really good youth coach who runs the youth team just in case it makes a difference, but otherwise I always use general coaches. As a big club, who can afford to have youth coaches, it's easy to find general coaches with decent Working with Youngsters who can train both the first team and youth teams.

As Brian said it's facilites and reputation along with luck that determines how good your youth intake is. There is no guarantee the good facilities, high rep and good caoches will produce any players that are good enough for the first team. Good players can be generated at any level of youth facilities and reputation, it's just more likely with higher reputations and facilities.