question about item requirements

i have a warrior, and i have a shield that i want to use, its armor +9 and says it requires 4 tactics

does this mean i need my tactics to be level 4, and if its below 4 i willl get 0 armor from the shield? how does it work

i also have an axe that says 6-27 damage, requires 11 axe mastery, i currently have axe mastery at 7, but i equipped the axe and it seems to do good damage, so what exactly do the requirements mean?

you will get less than the stated figure sometimes much less

This page should also help: http://www.guildwarsguru.com/content...nics-id674.php

ok so basically the requirement just means u need that to get the full stats, but u can use it even if u have less any time u want, thx