Hiding headers

[Samuel Sinayoko]

Dear list,

I've just been starting using Gnus and I'm really enjoying it. 

I'm having problems hiding headers though. For some reason I can't hide
headers at all. When I do `W W h', it has not effect.

I've checked that with C-h v that "gnus-show-all-headers's value is
nil".

I was initially trying to hide the long To or Cc headers. To do so I had
added this to my .gnus,

(setq gnus-treat-hide-boring-headers 'head)
(setq gnus-boring-article-headers '(empty followup-to reply-to long-to))

but it had no effect.

Thanks for you help!

Sam