The SC has had nothing like the effect on the game as a whole that RU turning pro did. That removed a huge source of outside backs from league (plus a more minor problem of some players lost to Union). If SL clubs had no cap, they'd still struggle to sign union backs given the disparity in income between the top union and league clubs and the profile union has. Cap or not, there's no way clubs would be signing up union stars as they used to.
When you look at GB's best outside backs over the past 30 years, a hell of a lot were from Union. I think that covered a lot of deficiencies which were actually there in terms of junior development.
In addition moving to summer rugby meant the loss of short-term signings from Aus (often the superstars who wouldn't sign full-time) and also the loss of chances for Brits to guest in Aus (possibly a bigger problem for GB). That was a move that had to happen though.
Add to that fact that Wigan fans are looking through cherry-rosed spectacles at an era when they were the only game in town for years, and the whole SC argument falls on its . How 'great' were games between lower placed sides during Wigan's dominance? No better than now I'd bet.
And you CANNOT ignore the near death of Leeds, Wigan and others as a direct result of misuse of funds when discussing the salary cap.
What is holding the game back in England now far more than the Salary Cap is a dependence on frankly very poor Aussies/Kiwis. And look to Wigan as the best example of that. Get rid of your 5 out of 7 overseas backs (if that figure doesn't make everyone shake their heads then nothing will) of whom not a single one is a star, and replace with two real top flight Aussies and youngsters, and I'd bet that Wigan would be no worse than they are now.
If your club chooses to spend cap money on the likes of Carmont, Phelps, Leuluai, Richards and Roberts, then I'm afraid you deserve mid-table mediocrity and to forever wonder why you don't win anything and why most games you watch are p*ss poor.
Unfortunately fans are as much to blame as coaches in this. I can actually understand a coach, who's job is almost permanently on the line, being conservative and saying 'bring in an Aussie' rather than take more risks with youngsters. That attitude will filter through the whole club, and make sure that junior development is not taken as seriously as it should be.
What's less forgiveable is us fans demanding instant success and complaining that our clubs aren't signing so-and-so from Australia. And before anyone asks, I've been watching Leeds for nearly 30 years, and have taken nearly as much enjoyment out of watching young British players succeed in the team as win the Championship. 2004 excepted.
