I just upgraded to Secrets of Faydwer for one of my accounts and I noticed something a bit evil that they did. If you buy gear with heroic stats on them you will NOT get the stat bonus until you activate SoF on that account. I’m wondering what other stats do not take effect until you activate SoF. The extra avoidance, etc. on the tradeskill augs I think this is the first expansion that Sony has done this on. Sure you were limited before on what gear you could get from an expansion if you didn’t own it but I have never noticed gear not giving the full benefit until an expansion was ordered before.
My guess would be it is a code limitation. The bonus is applied through SoF program code and that code is not in effect until the expansion is activated.