I had a test with another archer. My luc was good enough i think. He crit all the time on me and i didnt crit once at him..
You haven't really answered the questions people have asked so I think a few explanations are needed to clarify things.
When you try to hit someone the game makes a couple of decisions.
First decision is whether or not you actually connect.
It will check whether your target has any untouchable effects
Then it will compare your dex and any increased hit chance buffs (like conc nos) against your target's dex and any evasion buffs.
you have connected, then
the game decides whether your hit is a critical one or not.
This will be decided by comparing your luck and any crit buffs (like KO nos or bash) against your opponent's luck.
There are a few complicated formulae in there, but basically if your opponent has a lot more dex than you then you will never even hit them and the luck comparison will never take place.
What people have been asking is whether you are hitting your opponent and not getting a critical hit, or are you missing altogether?