Toriyama himself tends to complicate this a lot. Sometimes characters can sense someone’s hidden power just because.
The lesson I take here is, we’re better off not thinking this. We don’t know enough about this stuff to get conclusive answers.
This has nothing to do with hidden power.
There's no denying that power is one representation of ki. The issue is that we're conflating ki output with a user's total ki and energy. Ki is a representation of both power and total energy but they are represented in different ways. The Z Senshi do refer to ki when they discuss power but the only thing they can sense is ki output, not total energy. Therefore, just because ki is a representation of power does not mean it is not represented differently for energy.
We know this to be true because ki suppression does not reduce overall energy but does reduce ki output. That is only the case if ki is used differently to represent both power and ki. Therefore, just because ki can represent power does not mean it is represented differently when we talk about total energy.
This is a point that is completely being ignored for reasons that I don't know. There is absolutely no proof that there is a 1:1 relationship between power and energy whereas there is plenty of proof that drops in energy do not necessitate an equivalent drop in power. Case in point would be Piccolo's battle with Android 17 where Android 17 only mentioned that Piccolo's power would start to drop because his stamina was starting to diminish after multiple clashes. That would not be the case if Piccolo's power had been dropping from the onset.
This isn't that complicated. It is very simple to understand.
@FeatsofPower literally stated that you can consume energy while maintaining nearly maximum efficiency. Gamma 1 explicitly told Gohan that he was designed so that he could maintain full power while consuming energy far longer than organic organisms due to their inherent design which implies that organic organisms can maintain power to some capacity while exhausting energy. The Gammas just do it better.