Singularly unique

Is the phrase "singularly unique" acceptable or is it a tautology? If it is acceptable, why is it acceptable?

Not acceptable! Not acceptable! Arrrgh!

"Unique" is an absolute. Either something is unique or it's not. There aren't degrees of uniqueness.

Definitely not acceptable, almost as bad as my "increasingly more" comment in a previous discussion! However I have heard it said before, but that doesn't make it ok.