"Your complaint (if taken seriously) amounts to intellectual nihilism, a denial that scientific theories are testable."
Not at all. My whole point is for a hypothesis to be truly scientific, it must be testable.
Hank
Well, good then. It's just that you were complaining about examining the evidence (putative transitional forms) in light of assuming evolution to be true. But this is exactly how you test a theory. You deduce its implications as to what kind of facts you should observe -- and not observe -- on the assumption that the theory is true.
If evolution is true, and the fossil record is not too drastically imperfect (it isn't), then we should find fossil forms that are intermediate between the Families, Orders, Genera and so on that were created purely on the basis of living forms. This is exactly what we do find. The series of transitionals linking reptiles and amphibians, for instance, is so good that it's entirely arbitrary were you draw the line. Although living reptiles and mammals can be distinguished by dozens and dozens of marked skeletal traits, the fossil forms can only be separated by the trivial detail of a single articulation in the jaw. Literally every other feature is either intermediate or appears on both sides of the "line".