So there's no way that we could have tracked down this problem as in both of the code extracts you gave us, the form method was contained in a variable.

I (together with, I expect, most of the people who tried to help you) assumed that the same variable would have the same value in each example. Another good example of why it's a bad idea to make assumptions.

Update: Actually, imp points out to me that we didn't make assumptions. You showed us code that had "post" for both methods.