This is really helpful everyone. Thank you. The school by the way had assured us that he wouldn't be disadvantaged just doing 1 facilitating subject, as I'd really worried about that but they said it would be fine as all his subjects were well respected. So I hope that's the case.
The reason he's thought of joint honours is that he loves some aspects of his subjects but not others and wondered if somehow he could combine the most interesting parts into a joint degree.
He really enjoys the ethics parts of RS and Philosophy and philosophy of mind/morality, the 'big' questions, the crossover between philosophy and psychology but he isn't so keen on the history of various religions, logic, epistemiology - the 'dryer' stuff.
He's really good at Eng Lit (and was also great at Eng Lang at GCSE) and writes well but - isn't so keen on what a large proportion of RG Eng courses focus on - early English texts, the classics etc. He doesn't want to have to study an ancient language if he did pure Theology, which many courses seem to expect.
He's one of those students who can draw from lots of areas of knowledge, rather than focus down and get absorbed in one specific subject or topic - and come up with new ideas or ways of thinking about things.
I think he'd not cope well with juggling the potential clashes between two degree subjects and all the rest of university life too. So that seems to leave him considering either Theology, at the moment or English.
His school will advise him later on but he wants to start thinking more about this now. Knowing him so well, I can't see him happily fixed on either of those as a single degree subject and he has absolutely no idea at all about what job he might want to do after uni. So that doesn't help either.
Anyone here know much about Theology degrees? He's probably ruling out Philosophy, as her thinks it'll be too logic-based and he's more the creative/artistic type.