Wouldn't a 1 MHz scrypt ASIC able to mine this at 500 KH is everyone is hashing at half their max? What is stopping from small gridseeds to scale?
haha, fortunatelly not

ASICs are out of this..
they are built directly to be used on scrypt nothing else.. they are dumb devices doing just one task..
GPU can adapt to different n factor in this algo which will increase through time.. so even if they started to design new asics to VTC right now (and it is not really simple process), by the time its out, VTC may have higher n factor putting them again out of game

This is why VTC is and WILL be ASIC resistant...