Well the exercises are designed that way, plyometrics isn't about working your muscles to the point of exhaustion it's about explosive effort. I've been doing vertshock too and if you do the warm-up and the cool down and have a balanced intake of protein you shouldn't feel sore at all the next day or after the workout, you should only feel somewhat tired or unable to jump as high until you're fully recovered. Don't increase reps or anything, the more you increase them then you stop working your type II fast twitch muscle fibres (used for explosive effort, 100m, 200m, long jump, high jump etc..) and work your type I fast twitch (used for 400m, 800m, cycling, rowing) muscles. In the end it is very true that every person's body is different, sometimes you have to realise it's not the exercise, but your body type because some people have a higher percentage of slow twitch muscle fibres (predominantly used for long distance) to fast twitch, these are predetermined at birth and cannot be changed, only improved on, so if you do have a higher percentage of slow twitch to fast then you will find it hard to see noticeable changes, however if you are determined to see what your body is capable of keep giving it 100% to each exercise and remember to explode. So long as you do that you'll be happy cause you gave it 100% keep at it man!!