While what he said may be true, what I was looking for was the intent. Some powders are formulated to be low flash like Accurate #5, 7, 9, or BE-86, etc. Then you have some like True Blue that aren't real flashy (a good thing), but aren't sold as being low flash.
I loaded some power pistol up in my 2-5/8" 627 in 357 mag and the white flash was about 12" in diameter.
I ordered some IMR blue so I will report back in a few weeks after I run it. The price was too good to pass up.