The possibility of tethering going down is enormous, because essentially it is a real money alternative to the USD as its developers have said.
In addition, tether can be made too much and unreasonable, causing its price to become unreasonable and diminishing - just like today happened on bitfinex.
The current tether is like a balloon that is inflated and can explode at any moment.
So I think staying away from Tether now is a wise move.