Barbarian observes:
You still don't get it. There is no magic bullet against science.
But the theory of evolution isn't a scientific theory.
Because Darwin's hypothesis was testable, and made predictions which have been repeatedly verified, it is a scientific theory. Perhaps you're not familiar with what a theory is in science. Learn about it here:
A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on knowledge that has been repeatedly confirmed through observation and experimentation. Scientists create scientific theories from hypotheses that have been corroborated through the scientific method, then gather evidence to test their accuracy. As with all forms of scientific knowledge, scientific theories are inductive in nature and aim for predictive and explanatory force.
http://en.wikipedia.org/wiki/Scientific_theory
For something to be considered scientific, we must be able to apply the scientific method to it. The scientific method involves observation and experimentation.
Hence, one can test Darwin's theory by his predictions, such as:
"There should be fossils of whales with functional legs."
"There should be fossils of fish with functional legs."
"There should be fossils of transitionals between birds and dinosaurs, but not birds and mammals."
"A population moving into a new environment will change over time to become more fit in that environment."
"Humans will be found to have first appeared in Africa."
and many more. Because all of these and more were later verified by observation and experiment, scientists consider the theory of evolution to be one of the best established theories.
The experiments involved must be designed in such a way that their failure would prove the theory false.
Indeed. So if a transitional between birds and mammals was found, or if DNA analysis showed frogs more closely related to humans than humans are to apes, or if any of the above predictions turned out to be false, it would have shown evolutionary theory to be false.
But of course, none if it did. Even more impressive, none of the things that shouldn't be found, if evolution is true, have ever been found.
Nobody has ever observed evolution from one species to another,
The first directly observed case was about 1914. O. gigas from O. lamarckania, but a polyploidy event. D. miranda was another example of an observed new species.
And no scientific experiment could ever be devised that could test evolution.
See above. Lots of other ways. I'm sure you can think of a few yourself, if you tried.
In addition, the theory itself is designed in such way as to be unfalsifiable.
See above. Lots of other ways it could be falsified. Haldane's suggestion of a rabbit in undisturbed Cambrian deposits, for example.
That alone makes it unscientific.
Would have. But as you see, every time we test it, the test verifies evolution.