Thanks for your comment. I'm Nick from Singing Canary and I produce all the Art of Audio Recordin tutorials. In answer to your complaint:
Technically you are 100% correct. As you know, to the letter of the law a decca tree :
was originally used in orchestral situations, fitted on a tall boom and suspended high up in the air, roughly above the conductor. Three separate stands were sometimes used to set individual heights. A Decca Tree setup includes 3 omnidirectional microphones in a "T" pattern. The stem of the T faces the orchestra, and the left and right mics are placed about 6 feet apart. The third is placed 3 feet out and centered in front. To mix, the side mics are panned hard left and right, and the output of the centre mic is then sent to both left and right channels. The level of the centre mic is set sufficient to fill in the centre "hole" left by the widely spaced outer mics, but is not so high as to cause an overall mono sound to the recording!
We discussed this when filming. We had reservations when titling the film, whether to name it as such. Greg Haver the producer had an engineer friend who was at Decca in the 60's and the inside view from there, was that there were no hard rules other than 3 omnis in a triangle! Apparently, the engineers enjoyed the precision debates outside the studio as inside, it was very relaxed and organic, based on the sound. Over the years, some engineers take the view that a 3 mic omni set up in a triangle can be called a decca tree.
We argued the toss and thought about calling it Decca Tree Variation or even Greg's Decca Tree but in the end, we were happy that it could run. However, you are right, and we are wrong! We will rename it and will do so today to Decca Tree Variation.
I hope this hasn't ruined your enjoyment of our tutorials. Thanks again for your feedback.