How do you know you have a good catch?

[TIJoe]

Now we know all the theory about having a good catch -- high elbow, pulling over a barrel, early vertical forearm etc. However, when you are swimming, you might be thinkg of high elbow, EVF, but reality might be quite the opposite. So when you are swimming, what kind of feedback, if any, would tell you with some certainty that you just have had a good catch?