Usually I'd say it's not worth it, but given that this guy is only halfway through his 19 year old season and he has such good big guy skills, esp the 10 in ID, makes him worth holding on to. Additionally, he already has the jump range so I'd say give him a season's worth of JS to get him up to respectable or so.
I'm sure you can find some other players on your team who need JS training and you can always mix some other types of training in there as well.