[squid-users] refresh_pattern and same objects

[FredB]

Hi all,

I think I misunderstand something but why refresh pattern is not useless ?
I mean the objects are supposed to be delivered with instructions from the web server, lifetime, creation time, etc 

I thought, and it seem I'm wrong ?, that squid check the HTTP header when the object seems expired (HEAD request), if yes the object should be refreshed, or not, when is life is ended ?

Force a long refresh pattern is not dangerous ? For example with some security files. 
 
Regards 

Fred