Maybe it's just me, but I don't believe a reptile will ever become "tame". They can "learn" to accept being handled from time to time, but it's not a pet in my humble opinion - a P. vitticeps - just like any other reptile, amphibian and so on - is a hobby-animal. Excessive handling leads to stress; e.g. taking him out of his normal environment (the enclosure) every day. If you've only had him 2 weeks he's nowhere near to being settled 100 % yet. But yep if he can get away, he will. I'd handle him a bit in the enclosure, and when on occasion taking him out of the enclosure doing so with a pretty firm grip.
I would also try handfeeding him his favorite snacks in the enclosure. This way he will learn to "link you mentally" to a feeding dispenser so to speak.
I personally only handle my reptiles, when cleaning out the enclosure, taking them for a check-up at the vet and when giving them an oppurtunity to drink from my hand at the sink.