10 x 800 is not necessary espescially in the summer.
As long as your three quality sessions cover 400/800 pace, 1500 pace and 3k/5k pace you will be alright. Although the target pace should cover a good chunk of distance ie last summer just before I ran 3.54 for 1500, on tues I did 4 x 400 off 1 lap jog recov' in 55,55,54,53secs, then a few days later my 1500 sess was 2 x 1000 off 2lap jog in 2.34 and 2.33 - painful sessions!
Does take a while though to get your time down so race often over 800, 1500 and 3k. My first 1500 of the season was about 4.12 and each time I raced the time came down - so be patient and the sessions will kick in. Very hard to concentrate.