Was thinking, the record of standout performances in Ken Loach films cannot be a coincidence. I haven't seen all his films, but lead performances that stand out in my mind (which is not to mention all the great performances by actors is in smaller parts) include:
Peter Mullan as Joe in My Name is Joe
Bruce Jones (never acted before) in Raining Stones
David Bradley (never acted before) as Billy in Kes
and Martin Compston (never acted before) as Laim in Sweet Sixteen
now add Steve Evets to that list. I'm sure there are others.
Ken Loach must deserve credit for getting these performances from these actors, which is not to take away from their personal achievements.
I did see a little show about Ken once, and the two bits that I remember from it was that a lot of the shots, including close-ups and intimate conversations, are taken from a long way away - could be up to 50m, and then a really strong zoom is used. This means actors can act without a camera up their noses, and so produce more naturalistic performances. This cant be done on a small set, but where possible it is.
Also, he withholds the script from actors and trys to get as many natural reactions as possible. For example, in Sweet Sixteen there's a scene where Liam is meant to go and stab someone in the toilet. They practice the stab scene, then go for a take, Martin goes in, then unknown to him all the characters who put him up to it, jump out the stalls and stop him. The reaction of surprise is totally genuine.
i'm sure there are lots more subtle things that go on too, but it really is an incredible achievement the amount of performances that come out of his films.