RE: how do I visit a file in info mode?

[Drew Adams]

> > So try `C-u C-h i' instead of `M-2 C-h i'.
> 
> That was it.  Thank you!!
> Completely unclear why it was necessary to change it, though.

Most changes are not strictly necessary. ;-)

The more common use of a prefix arg is as `C-u'. A numeric prefix arg sometimes
serves, like here, to provide a numeric value (or to provide some other
alternative behavior).

In this case, from the doc string (`C-h k C-h i'):

"In interactive use, a non-numeric prefix argument directs
this command to read a file name from the minibuffer.
A numeric prefix argument selects an Info buffer with the
prefix number appended to the Info buffer name."