I disagree. When one is only concernde about the order of magnitude, it should be given as 1*10^2 mya or as 0.1 bya. What the OP said is analogous to saying that one's grandfather died at the age of 100, when in reality he only lived to be 66.

I don't know if it will make you feel better or worse, but when writing the comment I looked up wikipedia, saw "66", thought "eh" and wrote 100.

If my grandfather had made it to 66 million I would have done the same thing.