If we're going to use big words we really ought to know what they mean.
Straw Man ArgumentIt's easy for the perpetrator to knock down their own Straw Man because they can make the Straw Man themselves. It's a tailor-made position for the person using it. Usually, the person using the argument will knock down the unrealistic caricature in Step 2 as quickly as possible, and then proclaim that the opposing position has been demolished because they were so cleverly able to knock down their own manufactured Straw Man.
They pretend that the Straw Man is the real argument, not the ridiculous caricature they created with deliberate ignorance and made-up facts. A real counter-position could cite facts to support their position. You can point out to them that they just knocked down their own caricature of evolution. Not the facts that support evolution. Straw men are ineffectual in that they leave the facts untouched.
Unfortunately, this tactic fools a lot of people because it can be subtle. In the case of evolution, an anti-evolutionist can take a slightly ridiculous point of view that seems born out of ignorance of science or fact. They then refuse to listen to rational facts, and escalate the ignorance until it's a full-blown Straw Man. This is a related tactic called deliberate ignorance. It will also include attempts to generate numbers out of the air to defend a Straw Man position.
This is one of the most unethical and cowardly of debating tactics, since the person using the Straw Man has so little confidence in their own position that they cannot even address the real position of their opponent! At the heart of the Straw Man Argument is deception.