Specifying a general expression requires recognized legal evidence. Mere personal preference—“I think this situation should not count”—does not amount to takhsis. The marginal note considers further specification where a valid proof has been established.
Sound sequence: identify the general text and its domain; investigate the specifying proof; determine the excluded cases and the remaining scope.
Without this sequence, one may either extend a ruling beyond its proper reach or arbitrarily narrow the scope of the text.