3zo should open fold upto depth of 3

According to the documentation for folds, the command 3zo should open
folds to a depth of 3. When I move the cursor to a top-level fold and
enter 3zo, it's as if I only entered zo, i.e. only the top level fold
opens. I have foldmethod=indent. There are in fact subfolds at
levels 2 and 3 within the top level fold.

Can anyone corroborate this behaviour? Am I misinterpretting the
help? How can I get the effect I seek, i.e., open a fold by a certain
depth?

--
--
You received this message from the "vim_use" maillist.
Do not top-post! Type your reply below the text you are replying to.
For more information, visit http://www.vim.org/maillist.php

---
You received this message because you are subscribed to the Google Groups "vim_use" group.
To unsubscribe from this group and stop receiving emails from it, send an email to vim_use+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.