toggle-viper-mode strangeness

[Giorgos Keramidas]

It's been several days since I updated cvs-emacs here, so forgive me if
this is fixed already.

Isn't the following in `toggle-viper-mode' strange?

        ;;;###autoload
        (defun toggle-viper-mode ()
          "Toggle Viper on/off.
        If Viper is enabled, turn it off.  Otherwise, turn it on."
          (interactive)
          (if (eq viper-mode t)
              (viper-go-away)
==>         (setq viper-mode nil)
            (viper-mode)))

Looking at the indentation I'd expect the if expression to end where the
arrow points, but it doesn't.  Or is an implicit (progn ...) added
automatically by Emacs around the third ... N-th elements of the if
expression?