The skill levels are not discrete. A respectable skill isn't a skill level of 7 proper, but could be anything between 7.000 and 7.999. Training increases the skill even if there is no noticeable pop. That's called a subskill. In your case, many subskills were very high and popped after little (secondary aka cross) training. Still, now these subskills are low, and you shouldn't expect new pops in these skills all too soon unless you train them directly.