MidnightSkyline (big grin) One thing I learned in life is that if a person reads a lot about any one topic, the more that the person find different authors interpreting the one topic differently. All religions, all philosophies, and all sciences are the same, with different authors speaking the same words while meaning different definitions.
Years back I did a sizable quantity of reading about religions, philosophies, sciences, and 'new age' stuff, and yep, all of the authors used the same words while meaning different definitions.
It is like the 'Chinese Whispers' game: the first person whispers a sentence in the second person's ear, the second person whispers the sentence in a third person's ear, and so on until 30 individuals have been whispered to. When the last person is asked what they were told, they will reply with a sentence that is nothing like what the first person whispered.
It is human nature. All words only mean what they mean to each individual. Speaking words without definitions will always result in Chinese Whispers. 'Twin flames', 'twin souls', and 'split souls' only mean what the words mean to each individual.
Speaking strictly for myself, the heart dictates what is compatible or incompatible. A heart's burning tone that is as a symphony of slow low-toned viola de gambas, is not compatible with a heart's careless tone that is as a rock band of fast banjos. Whatsoever name a person chooses, still will the compatibility of heart tones dictate how well the individuals harmonize with each other.
As dictated by the laws of Nature, two souls cannot fully harmonize unless they both reciprocate what the other gives. Two souls can go through life comfortably without conflicts, but when two souls both sing the same song while reciprocating, the reciprocation will create a new symphony that is very beautiful.
For myself, the ultimate love story is of two souls that cry of a similar depth of heart, and upon finding each other, each surrender their heart, life, and soul to the other. Without desire, purpose, nor choice, the compatibility, reciprocation, and harmony are tremendously beautiful.