Do you remember All You Zombies? No? Well, that’s not surprising. It was first published in 1959 and it isn’t about zombies, but about a man(sic) who is every character in the short story, by means of time travel and a sex change operation.
Even Lawrence Smythe, the lead character in Double Star, who starts out an anti-Heinlein character, becomes a true Heinlein character by the end of the novel.
Before we decide that this is a fault, lets look at the names Heinlein uses.
Valentine Michael Smith
Woodrow Wilson Smith
Johan Sebastian Bach Smith
Wyoming Knot (All right, that one was a bad pun that doesn’t fit the pattern, but I had to include it.)
Thomas Paine Bartlett
Patrick Henry Bartlett
Daniel Boone Davis
Andrew Jackson Libby
D. D. Harriman (Think E. H. Harriman, tyrant of American railroads.)
Good God, what bigger clue do you need? Do you think Heinlein couldn’t think of interesting or unusual last names? Or that he couldn’t think of names not already used by famous Americans? These are American everymen. (Or women. Or both, in alternation.) No wonder they all look alike.
They’re also Bob Heinlein clones. And that’s okay by me.