The real problem here is that you're gay.
I agree.
What a fucking homo.
Why all the rude comments? Somebody is merely asking for help, and all you have are criticisms of one's sexuality which is completely irrelevant.
Now to answer your question, I would say because text responses are a completely different style of writing! And they are hard! Whereas context gives you the FREEDOM to choose and master your own style of writing, and analysis is mainly self explanatory and straight forward (who can't pick up an angry tone...), text responses aren't that clear cut.
You may be a great writer (demonstrated by ur skills in the other two AOS), however you may not have the MINDSET to interpret texts, and characters, themes etc.
Unfortunately IMO you either have this skill or you don't, however I do knw that the more essays you write, the more samples you read, the more times you read your text, the better your text responses will be!
Make sure you read your texts 3-4 times in a year, once on the dec/jan holidays, once before a SAC, once between THAT SAC and the exams, and once before the exams (for year 11's going to year 12)
But unfortunately it might be to late now =S
EDIT: Didn't know you guys knew each other, my bad