I'd say it depends what combat level you are. If you've had the account for 3 weeks and have like 60 str/40combat you may aswell restart. On the other hand if you've trained for ages and are higher level, just keep it.
it doesnt work that way it would decide from a 30 30 and a 30 0 . (which would be rare from 5 lvls considering that most pkers have 60+attk) I just realized that ppl with accounts with 80 str might still be noobs. No offence pal but if you didnt know how def works you are 1.