If there are "schools of thought" about this, there shouldn't be. KM 184s and KM 140s are identical in acoustical design and sonic character. The capsules for these two models are built in batches and inserted into capsule heads for the one model or the other with no difference as to how they are manufactured or graded or selected or anything else.
Apart from their slightly (ca. 3 dB) different dynamic range specifications, the electronics are sonically identical as well, i.e. neutral in both cases. The main difference is functional: The capsule head of the KM 184 contains no active electronics, and so can't be used with Neumann's extension cables (etc.) for the KM 100 series. (In the KM 100 series the capsules are attached to a small, cylindrical barrel containing a small printed circuit board with some active circuitry mounted on it. This is why, for example, the replacement capsule head for the KM 140 has the Neumann model designation of "AK 40": The "A" stands for "active". The accessories that can go between the KM 100 microphone bodies and their "active capsules" are in fact completely passive.)
If the two models seem to sound different to anyone, it would only mean what it would mean if one individual KM 184 sounded different from another one, or if one KM 140 sounded different from another one: individual sample variations (or perhaps one or the other microphone is out of spec), and/or the gains of the two preamp channels might need to be matched better to the respective sensitivities of the microphones. It is amazing how many subtle and not-so-subtle differences between otherwise identical components vanish when levels are properly matched.
--best regards