Crossfire is bad?

So i've had crossfire 2gb hd 6950s for about 1 and a half year now, and my experience with has been that there's been bluescreens (I run with 3 1920x1080 BenQ monitors aka eyefinity) sometimes, my skyrim still lags a little, but I have a alot of hd texture mods and etc, but I still think that my two 6950s should damn well handle the game smoothly, and that's just not the case, same thing with Guild wars 2. 

 Im experienceing these lags or stutterings in my 3 most played games, guild wars 2, skyrim (with lots of hd mods), and battlefield 3 *note I didn't lag at all in the begining of the battlefield 3 year, after some later patch by origin/EA I could just no longer play battlefield 3 smoothly on all high settings etc without lagging/stuttering (ofcourse Im not stupid enough to pick servers where I have bad ping). 


Now, in dota 2, its all fine, everything high and etc, but then again every single source engine game is realy realy well optimized (credit to Valve). Likewise for the new game Forge, Magicka, Tf2, AC Revelations,brotherhood and 2. I have deus ex:Human revo and witcher 2 installed since the christmas sale but I have yet to play them so i don't know how it goes in those games. 

Now my theory is that the 3 of my most played games are laging / stuttering , not because of my RAM (16gb) or  GPU , but because they are badly optimized and rely too much on my CPU ; A AMD X4 II Phantom 3.0Ghz (overlockt to 3.3Ghz). 


Am I right? Or am I wrong? I know for a fact that gw2 relies way too much on CPU power, why is that? Why aren't game develepors making sure that their game is alot more optimized to use the GPU power than the Cpu power before releaseing their game?

And as my final and title question say, is crossfire bad? My experience with crossfire has been both bad and good. 

might be the cpu maybe upgrade to a 3570k or fx 8320

For your video cards there is a slight CPU bottleneck, get at least what ragingh4vok says.

The problem with games that lag on CPUs is because they're either:

1. Badly optimized (usually only console ports)

2. Were meant for multiprocessing (quad core seems to become the norm if this keeps up)

Some games don't support multiple GPUs, as many old games didn't support SMP. Though in my opinion multi gpu has always been about money (optimizations, buy 2 instead of 1 ...), still it's become a viable option for games today, and a practical solution for multiple monitors, and when you actually need the power (professional 3d programs), so I don't despise it anymore.

With multigpus you gain a significant bandwitdth increase, processing power (extremely dependent on software). You also get higher power usage, more heat, more noise and software hassle.

if you get bsod, it isn't always dut to you gpus. update your vid drivers to beta

Last time I had a bluescreen was mayby half a year ago. ever since the latest amd controll center update, it's been fine.

how can you see that there's a bottleneck?

Bottlenecks are signified by averege 100% usage on CPU and significantly less on GPU, ~40-50%.

Also, little freezes and same fps on all settings are also symptoms.