Question about completion behavior

[Ergus]

Hi:

I am wondering if this behavior is totally intended and consistent.

emacs -Q
M-x c<tab>: shows-completions
o<tab>:     updates-completions
mp<tab>:    updates-completions
i<tab>:     inserts l and hides completions??

I would expect that in this case the last tab inserts l and update
completions as well. And have the current behavior (hide completions)
only when completion-auto-help == 'lazy or when the completion is exact
and unique.

In the code that hides the completions there is actually a comment about
this:

;; We could also decide to refresh the completions,
;; if they're displayed (and assuming there are
;; completions left).

Is anyone working on this?

Was all this behavior intended or how do you propose to solve this?