Well DR/HA are rather low on my trainee because I focused on other skills first (and with 203 cm training OD takes some time)
If you only push DR/HA and especially JS he will cap quite soon (JS is by far the most expensive skill cap and salary wise for SF) while Blocking costs nearly nothing
You can also say PF training is fast if you only train IS/ID/REB & One on One .. while training one with JR/OD/PA takes quite some time .. it depends on the build .. and I like balanced SFs more than JS/DR/HA Monsters ;)