From that same website, check out this page under the header Blumlein δ (delta): https://www.phaedrus-audio.com/shuphler3.htm The 22cm (instead of 20 cm) is given in case the baffle is seen as optional. In the table further down that page the same Blumlein Shuffler is recommended for: near spaced omnis, near spaced cardioids, near spaced hypercardioids, binaural microphones, phased array cosines (Faulkner). The whole idea of the shuffler is that phase differences of the lower frequencies between L/R channels are converted into intensity differences, in order to get the correct bloom of widely embracing low notes. From my experiments I have learned that it may be useful to angle the capsules out a bit (no more than 45 degrees) in order to profit from the difference in frontal impact representation of the higher frequencies.