Too many theoretical variables. You okay at that

I'm okay with the time it takes to chill. But the study in Zymurgy says they're getting it done in 10 minutes vs. my 14 minutes.

The variables:

They chilled 5 gallons, I did 5.5.

They used a 46'x3/8" coil. I use 2 separately-fed 25'x3/8" coils. Theoretically, this should give mine an advantage, at least enough to make up for the slight difference in volume.

We both used 65f water to chill.

I circulate the wort continuously, in the opposite direction of chiller flow.

My chiller flow rate is 3 gpm. So is theirs.

So how do they chill so much faster? Or do they? Perhaps the article is based strictly on calculations, with no scientific data, and is really just theoretical bs?