Condemned Criminal Origins is a first person melee game that came out in 2005. I played the original Condemned about a month ago, and you can watch Kessler and Steve play through it on their Fear Gauntlet. One of the big things in the first person melee combat in that game is timing your blocks and counterattacking. The enemies will try feints and weaves to get you to mess your timing up, blocking with the proper timing is big. You could also pick up guns and use them, with effective results.
Zeno Clash is a first person game focusing heavily on melee combat. that came out in 2009. Beyond just allowing you to punch, they added several gameplay benefits like dodging, multiple attack variations, and lock-on targeting. You could also pick up weird ass guns and use them.
Oblivion is a first person RPG that came out in 2006, and the same devs released the similar Fallout 3 in 2008. These games had both melee combat and shooting.
The point is, every one of these games, even Fallout which almost no one played using melee weapons, featured a block button. So that the player could actually play defensively instead of just mindlessly hopping around as enemies sprinted at them. The block introduced timing and player intelligence, reading the enemies' behavior. So why does a first person melee combat game that came out in 2011 not have the same functionality as one that came out 6 years ago? What gameplay reason is there to not allow players to block attacks? If they think popping in and out of range, hoping that the hit detection will work for once and register your attacks, they'd be woefully ignorant of what constitutes fun. Maybe they aren't, maybe this is my fault, maybe there's a block button not listed on the controls screen, and I'm just crazy. But considering we have a button for "Drop weapon" but no block, I have to doubt it.
To quote another nerd who plays video games that make him angry; "What were they thinking?"