Alexander Pruss, a philosopher at Baylor, comments on physicists' notoriously casual attitude towards mathematics and notation. This is right on. Like the first commenter, in school I remember the snide remarks the math and physics profs would direct at each other on this subject. As a physicist at heart, I pretty much adopted the more casual, plug-n-chug attitude of the physics professors. I suppose engineers are even worse.
This brings the unreasonable effectiveness of mathematics to a whole new level. Math still works even when you are not really doing it right.