I'm not asking because I want a trading vehicle but because I understand the risk.

And if the risk is going to be unloaded onto the user, it isn't really removing the volatility. It's simply delaying the effect until exit.

If it is going to be "stable" pegged to the USD, then there has to be a backing asset that moves with the USD. 

If the backing asset is Bitcoin, then there will need to be inflows/outflows with the price changes.

And that's what is not really explained.

If I buy $1 of this token ecash, how do I know I still have $1 a month from now.

Granted, using any mint comes with risks and is a custodial solution, but a dollar peg seems to add more risks on top of that and I haven't seen how that risk is yet mitigated.