Like a Sherman but not a Sherman.

When is a Sherman Tank not a Sherman Tank? Most times a Sherman is a Sherman, but this time things appear to be different. The old  adage of "if it looks like a duck and walks like a duck means it must be a ...." might not apply in this situation. Sure it looks like Sherman Tank but there doesn't appear to be enough of it. If anything it appears to be a bogey short of a full tread.