I don't understand how people can not tailor to some extent when they know what they are facing, but I don't understand how people CAN tailor in a competitive setting.
Generally in competitive settings you are at a tournament playing against people you haven't met before - how can you tailor to an army you nothing about? Especially when you are going to be playing other people who will have completely different armies.
If you are playing someone you play regularly and you know that they bring lots of terminators, why would you then decide to continue with your list that that is only equipped to details with a unit or two, you are knowingly putting yourself at a disadvantage.
But as people said there is a limit to how much is acceptable, a list shouldn't be tailored to wipe out an ary turn two (albeit that is quite a hard thing to do). I think tailoring is fine and actually very hard not to do if it is against someone you play refularly - in my gaming group we buy units all the time to deal with specific armies *cough* 2 mortis dreadnoughts and quad gun to get rid of a helldrake *cough*
Me: To be honest im amazed there isn't a chaos god of not revising or at least chaos god of procrastination
MidnightSun: There will be, when enough people do it. Y'know when the Eldar were all engaging in their hedonism and Slaanesh ripped open the Eye of Terror with his creation? Slaanesh will have NOTHING on the God of Procrastination, and his vile minions will carve the galaxy asunder in a thousand year reign of blood.... Tomorrow