Prot warriors have this wonderful mastery skill called Critical Block, and if Shield Block increases your Block chance to more than 100%, it also increases your Crit Block chance by the excess.

In short: Yes! Do everything to increase your Block chance up to 102.4%, because it also increases your chance to do a Crit Block.

From what I understand of Shield Block, you can be safe knowing the extra will be converted into Critical Block rather than wasted. Therefore you really don't have a problem!

http://www.wowhead.com/spell=2565/shield-block

Aww yah i almost forgot about that okay thank you, so would you guys suggest when i reforge to always get mastery besides when im getting hit and exp? Like take off parry rating for mastery or dodge rating for mastery? My parry and dodge rating is pretty low like 13.5% for both

If I'm parsing what you said correctly, and you're reforging *into* hit and expertise, you're probably following some outdated advice; you don't need to worry about those, and want to be forging away from them (this advice assuming you're raiding; if you're only running five mans, keeping hit/exp can be valid, but you still shouldn't need to reforge *into* them.

The basic reforging strategy for Warriors and Paladins is fundamentally the same, but slightly easier for warriors due to one talent. Basically, keep your dodge and parry ratings as equal as possible, and don't worry about accounting parry rating granted by raid buffs, as Hold the Line makes parry slightly more valuable than dodge, and then push for as much mastery as possible. If you can reforge an avoidance stat to mastery without throwing that balance jarringly out of whack, do so.

Just to be clear - if you're running five-mans, Hit and Expertise are still useful. It's not about threat per second, rather it's that you don't generate threat on things you miss. Having some Hit and Expertise is well-worth the hit to CTC in five-mans.

Raiding is another matter, of course, but all too often people don't realize that different content calls for different things.