The OP thinks light generated by LEDs is possibly responsible for odd coral growth patterns. Since these anomalies are not seen in all SPS tanks illuminated by LEDs, there must be other factors involved, but does not exclude the possibility that LED light is at least partially responsible.
If we believe the Seneye's PUR algorithm, violet and most blue LEDs have high ratings, some approaching 90%, while low Kelvin 'white' LEDs can be as low as 35%. If the tank has the 'Windex' look, PUR would be high but if intensity is low, the coral will morph (flatten) to become a better collector of light. This might be the case with the axial polyps of some Acropora species. If water motion is low (and in most aquaria it is when compared to measurements I took on reefs in Hawaii) the coral might not need to build a dense skeleton perhaps to the point of becoming brittle. Thinking out loud. A dangerous thing I do occasionally.
If we believe the Seneye's PUR algorithm, violet and most blue LEDs have high ratings, some approaching 90%, while low Kelvin 'white' LEDs can be as low as 35%. If the tank has the 'Windex' look, PUR would be high but if intensity is low, the coral will morph (flatten) to become a better collector of light. This might be the case with the axial polyps of some Acropora species. If water motion is low (and in most aquaria it is when compared to measurements I took on reefs in Hawaii) the coral might not need to build a dense skeleton perhaps to the point of becoming brittle. Thinking out loud. A dangerous thing I do occasionally.