b) Shorting the market (selling YOUR BTC)
And give me back 110% of it each year. At cheaper prices of course, but how would they manage a btc bank run? They'd need to buy back and the squishy-squeezy sounds would reach the moon a whole day before the corn.
It's even worse... what would happen if they sell the deposited BTC's and they are unsucessfull in their shorting (the price keeps rising)? Default!
That's another reason it's not going to happen.
There's absolutely no way I can think of... unless a market of fully insured Bitcoin lending would exist and offered better returns than those 10% they would give you... which it doesn't.
Indeed. But if it did, their profit over 10% would be justified by swallowing the counterparty risk for me.
Again, *IF*... but it doesn't

Yeah, a fully insured 10% ROI would be great... but I can't think of any way that business model would be viable.
You could be glad if they don't charge you a custody fee for holding your BTC.
Reality, again. Thanks for spoiling my dream.
Sorry for that. You can get WAY more than 10% a year lending in bitfinex or polo..... But you can't have everything at the same time (high ROI with no risk). Even if it would be possible.... the world would turn upside down.... and then, everyone would be swimming in vast wealth.... and then salaries and prices for every product and service would skyrocket.... and then we would be at the starting point. Economics 101.