That's how they look. A freaky "tell" is in the B in LIBERTY when it shows up there. It's up and down like that. When you see it side-to-side, it's 99.99% of the time just strike doubling. In fact, I think the percentage might even be higher than that.
I noticed that they were strike doubling too when you find them also. That's why I was surprised that it was actually doubled. I have 2 other doubled die 1972's also.
Yeah, they're evidently more common than we thought. We must have over a roll of the '72s and '72-Ds combined. I don't think years ago searchers were looking for them very much, but now they're pretty much a standard check.
Have you tried to attribute which die it is? I see 10 listed in the CONECA Listings. http://www.varietyvista.com/01b LC Doubled Dies Vol 2/DDO 1972.htm Larry Nienaber