I can agree that the idea of quadrants based on which four functional orientations are preferred is a good way of looking at type relationships, but the same principle works just as well from an MBTI standpoint.
Group 1: NTPs & SFJs (Si, Ne, Ti, Fe)
Group 2: STPs & NFJs (Se, Ni, Ti, Fe)
Group 3: SFPs & NTJs (Se, Ni, Te, Fi)
Group 4: NFPs & STJs (Si, Ne, Te, Fi)