To be honest with you, NATS has around 3000 applications for their training (20 end up being selected), so bearing in mind they are denying 2980 applicants, I believe they have the authority to make the rules as they want without the need to change it (imagine paying all these people to come to the CTC to have only 0.5% being selected).
If you got Stage 2 coming up and are scared about the details of the aircrafts, just study them. I know it can be harsh to say that "If you can't handle the study materials, you shouldn't be attempting" but it's true, as said before, you will go under one year of intense training and if you can't bother to memorize 5 pages of aircraft information (that is more than essential if you are going to be handle them everyday), then I can't see you studying manuals of 200 pages each :/