There are still occasional niggles despite Human Revolution's strengths, however. There was a handful of instances where we felt paths were blocked off in spite of our skills and equipment, for example. There were the exception rather than the rule - a locked door here, a wall that needs a specific aug there - but they were noticeable. In every case, there may have been an alternate route that we just missed, but we never found it. The point? That Human Revolution is not infallible, though it has to be said that Deus Ex wasn't either.
The overwhelming majority of the time though, the system works superbly, with skills that let you be awesome whether you want to be a assault rifle toting commando or a sneakier pistol type, without ever making you feel like you're missing out.
...at least until you get to the bosses.
Whoever decided that a Deus Ex game needed to break up its action with four horrible, poorly designed Metal Gear Solid rejects needs to have their face slapped a permanent crimson. "Bad" doesn't cover it. These idiots are - by far - the worst things in the game, to the point that the inevitability of them showing up casts a shadow over the rest of the action.
The cover system usually works really well
The problem isn't the challenge per se, but the way the bosses get to flaunt the rules in a ways that simply don't fit the Deus Ex experience. Augmented agents? Fine. Being able to take a million shotgun blasts to their unprotected faces, amongst other magic boss powers? No. Human Revolution is hardly realistic, but it is usually consistent. Adding insult to injury, all four are introduced via FMV cutscenes in which even a full-on Captain Stealth version of Jensen idly wanders through the front door, practically whistling a jaunty tune, and all of them are fights to the death. You can't evade them, talk your way out, or even win via non-lethal KO. Regardless of how other games handle bosses, they're simply awful. Awful, awful, awful.
On the plus side, Human Revolution also introduces another, much more appropriate form of combat - debating. These are only used a few times in the story, but much more interesting, expanding on the usual dialogue tree conversation engine to make you work out an target's psychological profile as you try and talk them into standing down or helping you out. Clumsy writing often turns them into duelling monologues when they'd be better as quick and fast arguments, but it's a great idea - the only real shame being that there aren't more of them to help drill deeper into the main characters' psyches and motivations.
Find out how Deus Ex: Human Revolution uses choice to empower players in this video
As with the original Deus Ex, the more you peer and focus at any individual element of Human Revolution, the more you'll notice the cracks. The combat isn't the best you'll ever play, the dialogue not the punchiest, the stealth not the sneakiest.
But that's missing the point. Human Revolution is a game to take as an entire experience, where you can shift at will from having exciting gunfights to crawling around in vents, and where every victory is all the sweeter for knowing you chose to do it that way. It's a game which can persuade you to spend an hour painstakingly invading enemy territory undetected, not because you have to or because you're expecting any great reward, but because you feel Adam Jensen should be good enough to do it. It's a game where the 10mm pistol you pick up at the very start can still be your weapon of choice when the end credits roll, but where choice itself is your most powerful one throughout.
Above all else though, it's a game that paints a dark vision of the future you won't want to live in, but definitely shouldn't miss the chance to visit right now.