That's pretty silly. You should consider raising with quads on the turn just because your opponent might have a straight flush draw? Give me a break.

There is no chance I would ever fold quads under any circumstance, even with a four card straight flush on the board. If my opponent is showing strength a four card straight flush on the board and I have quads, I would consider it more likely he simply had a full than a straight flush and put all my money in the pot.