0.3 per week is a lot high and i don't think anyone could earn this amount without investing.. problem with pos is that you will need some money to start with, and maybe he cant invest on it because of that.
I think only managerial or supervisors are earning this amount and for an ordinary person like us, who are bitcoin people. I think this impossible unless you are an online gambling site owner, faucet site owner with a lot of advertisers or an exchange trading site owner.
Its achievable as long you see the problem in a different point of view.
Ther person has to achieve certain amount of sales or hit a service thats in demand. But this .3 a week varies on the valuation of bitcoin so it can be harder to hit if the price keeps going up the way they are.