Trump needs to hold back on that until the left makes a big deal about. That will educate a lot of the 90% of Americans who don't know 0bungle hasn't shown his long form either.
You are right. Let's say this stretches out for a few weeks and Trump then produces a long form birth certificate. Contrast this with the years, and millions of dollars wasted, hiding the form in Obama's case. Most Americans will realize something is fishy. And nobody will care that Trump was not clear about the difference in the 2 forms. It will have been a learning experience for everyone.