shiver: I suspect with younger children and writing (and I'm not a teacher), they find it difficult to think about what they're writing at the same time as remembering how to spell the words, so I doubt that they actually remember their errors anyway. Obviously, as they grow older, they should be expected to manage both.
I agree that it would be very bad if lists of spellings were not corrected, and repetition is used to learn the spelling words.
My DDs have always been fine at spelling tests, but remembering those words in other pieces of writing has come more gradually. I'm happy to see that year 6 DD is now getting it right most of the time in her work, and that she's being corrected when she slips up.
I'm not arguing for a lack of rigour in teaching practices, but I think teachers should be given a bit of credit for trying to devise ways of teaching children without turning them off completely.
And of course, as long as the SATs remain, it is very much in teachers' best interests to make sure our children can spell by year 6, as spelling is one of the areas in which our children, and their teachers, are judged.