He does reference Cinebench benchmark that does utilize multiple cores.
Even if it was Cinebench, that program relies quite heavily on GPU scores. Its fairly cheap and easy to add/upgrade GPUs on the Mac Pro. I wonder how it would compare if you just spent $300-500 dollars on upgrading GPUs on the Mac Pro. Also, it doesn't take into account RAM. Most of my work, for example, will not work on <64GB of RAM. If I based a home build around a i7 2600K, which can only support 32GB RAM, I'd probably only be able to do ~10% of my work's computational needs. I'm guessing that's what computerpro3 was using. It was probably over clocked as well, which is something even less people are going to be willing to do.
So to make a home build for my work, on the cheap, I'd be looking at a pair of AMD Magny 2.0s (or something similar). You're not going to build a hackintosh out of those, at least not without a lot of effort since Apple doesn't use AMDs. Even once doing so, when needing 96-128GB of RAM minimum, the RAM is going to be at least 1/2 the cost of the computer, no matter what platform I use. Then I'd need to run Ubuntu and Windows? I'm not very excited about that. And with this build I save maybe $800 on a $5K investment? So, is it worth something like 50 cents a day over the useful life of the computer to just have an Apple? I think so. And if I actually wanted to use Xeons, eh might was well just buy Mac Pro. At that point its only maybe 500 bucks difference.
Now I know I'm not arguing with you, its just rather absurd when people make claims of how the "true professional" is getting 60% increased ROI by building a hackintosh. For the exact thing this guy is doing, that MIGHT be the case (though I suspect he's exaggerating pretty much every estimate that goes into these calculations, this was the guy that was basing estimates off buying Apple RAM remember), but its not going to be the case for all of us. The lesson is that you just have to educated yourself to the available options and the true needs of your work. Then you have to weigh your PERSONAL preferences against the cost. Some of us might not want to build our own hackintosh mac pro, even if it saves us $500-$1000. And there is nothing wrong with that. Most of us have probably "wasted" far more money on cars we really don't need, or drinking alcohol, or going on a vacation, eating out, or anything else that comes down to the simple choice of how you value your time and money.
Plus, in my particular case, it wasn't my money, nor my final choice on what system was finally chosen. My boss wanted a system our IT supported (ie not hackintosh or Linux/Ubuntu), even if we could save a thousand dollars and I could probably do all needed maintenance, it was worth $1000 to him to just know this computer will not go down for prolonged periods of time for the next 3 years. I can't say that was the wrong choice and I'm certainly quite bit better informed on our particular needs that computerpro3 is...