the whole thing boils down to a question of justice or equality. Ginty always seems to drift - the half term off (ok there's reasons behind it, but you get the impression that Nick or Ro would have managed to drag themselves back), right at the beginning Lal says about Ginty being in an A even though she's not clever at all, she's really good at diving, yet always mucks it up, and she has generally useless friends - the redoutable Monica aside. So, perhaps it's a case of Mrs M feels that if gin has something she really gets into, it will work its way into all of her life, rather than just leaving her as pretty and somewhat vacant which is how some - Mrs Merrick for example - but not AF I hasten to add - seem to see her. Personally I've always loved Ginty, so was fairly happy about it all, but that's a "proper" reason for it.