Ive personally seen the following workout done, which is not too dissimilar to the prescribed workouts Daniels set;
5 x 1000m in 2.45 with 90 seconds recovery
2 minutes recovery
1 x 800m in 2.02
The runner had pb's of 3.58, 7.50 and 13.15 at the time of doing the workout. So the above workouts arent really that difficult, especially with the long recoveries. It seems reasonable that a sub 30 minute 10k runner could do 10 x 1000m in 2.52 with 400m jog recovery, so taking 4 seconds off that for a 13.44 runner is not mind-blowing.
The only issue I have is with the 3 x 600 workout at 800m pace. I have seen 800m runners and milers do this session, or a session such as 4 x 400m at 800 pace, but with slightly longer recovery (upwards of 15 minutes). Once a runner goes over 500m at 800m pace I don't beleive it to be attainable to run at the same pace 5 minutes later, after running, however slowly, 1000m. Or your 800m p.r. is soft.
E.g.
If you ran 3 x 600 at 1.52 pace (1.24 through 600m) this is probably more conducive to a performance of 1.48 when we factor in the lactate tolerance the athlete will need to attain such pace of the 1000m recovery. My point being that basically for everything under Mile training, the Daniels pace system isnt very applicable, due to the difference in energy systems that are used for the 800m.
I would recommend instead
Part a) - long distance race pace
1 x 600m at race pace (1.24)
15 minutes active rest (jogging/walking etc.)
Part b) - race pace/under race pace fluctuation training
1 x 400m at race pace (56)
200m walk/jog recovery
1 x 300m at -2 seconds under race pace (40.5)
100m walk/jog recovery
1 x 300m at race pace (42)
200m walk/jog recovery
2 x 200m at -3 seconds under race pace (26.5) with 1 minute recovery
200m walk/jog recovery
2 x 200m at race pace (28) with 1 minute recovery
300m walk jog recovery
4 x 100m at race pace (14) with 25m turnabout recovery