wait why are ya quoting me, I didn't say that.The above surprises me. The five senses as correlating with hit points? Constitution?
The five senses seem to overlap more with Intelligence with Perception<->Investigation. Detecting something includes recognizing what one is looking at, and making sense of it.
Or Dexterity, initiative checks, dodging, and precision.
Ultimately, what matters is the actual use during a game. One either notices something or not. Hence it is one check whether Perception or Investigation or Anticipation or Initiative to notice something coming. One check. One ability.