I am new to the Listener having started at the end of last year but have just joined the Times crossword club so I can access older puzzles.
I tried a few from 2008 and I agree with Dryden. The average difficulty seems about the same with some very hard and some, like this weeks, pretty easy.
I think I have completed all the puzzles this year correctly - though sometimes have needed help from this forum. Last week took about 6 hours. This week was less than an hour.