Of coarse evolution and all historical sciences can't be testable in most or all aspects. This should be self evident.
Yes the past is open to deduction from clues like a crime scene however the scientific method can not be applied to the big conclusions.
All one needs to pay attention to is whether the scientific method can and is applied.

This is why it seems every graduating class turns over some previously solid idea in evolution . Like PE.
Its easy when the original ideas had no tests to back themselves up.
Origin subjects are always about interpretation and then accumulation of data.
Just read carefully the posts here in this thread and you will see all the tests are based on premises themselves. Like fossil sequence and DNA stuff.
In the end origin subjects unlike laws of gravity can not be directly, repeatably tested. Origin subjects are like crime scenes. Here you will find the evolutionists are intel;igent, hard working Scotland Yard detectives. The creationists are Sherlock Holmes. Correcting and correct.