[Rd] ignorant question about Roxy- mode in ESS

[Ben Bolker]

  I am slowly getting up to speed/being dragged into using Roxygen in a
project. I'm wondering if there's a way to emulate the behaviour of C-c
C-p (Rd-preview-help) in Rd-mode (create a preview in a new Emacs buffer
in "R Help Preview" mode), but from an Roxygen chunk.  In Roxy-mode
there is C-c C-e C-t (ess-proxy-preview-HTML), which works to preview
the documentation derived from the current chunk, but it opens the view
in a browser window instead of an Emacs buffer. (ess-proxy-preview-Rd
previews the Rd file, which I find cannot be transitively run through
Rd-preview-help ...)

 (update: I can get it to work if I C-u C-c C-e C-r [to create a buffer
with the right name], C-x C-s [save it], *then* C-c C-p , but this (a)
seems like a lot of keystrokes, (b) creates a file that I then have to
go delete ...)

  Any ideas?  I'm not enough of an emacs-hacker to figure out how to put
these two pieces together.  Perhaps I have an old ess version (5.14)?

 thanks
   Ben Bolker