Is this just because consciously thinking "hip turn" is generally a good way to sort of "detach" the hip rotation from the rest of your throwing motion? By which I mean, is forcing a hip rotation just a sort of inorganic extra motion that inhibits the rest of your throw? I think this is akin to hitting a baseball in some sense; the great hitters get phenomenal core power transferred to the ball, but do so by driving through their lead leg/hip.
They're somewhat similar, but not really.
A strong baseball swing is triggered by a rotation of the back hip and the front foot pivot doesn't happen until you are attempting to drive the ball after contact.
also, what people tend to interpret wrong about this is that you are trying to swing the bat. if you were trying to throw the bat things would be more clear. the big front pivot dig wouldn't happen until the bat is about to leave or in the process of leaving your hand. hitting != throwing.
forcing a hip rotation puts the hip rotation out of order.
the hip rotation is a two stage process. the first hip rotation happens because of the x-step (or pivot hop step) or whatever type of run up you may be using (or not using). with a standard x-step if your left foot is facing away from the target your hips close and assuming your right foot is planted at an angle other than 180 from the target, your hips will naturally rotate during the weight transfer. how far the first rotation happens depends upon the angle of your plant foot. if it's 90 degrees, your hips will go from closed to neutral. if it's 45 degrees your hips will go from closed to open 45 degrees.
the big pivot dig doesn't happen until the moment (or slightly after the moment) the disc is leaving. this is the second rotation.
if you force a single pivot, going from the x-step to the second pivot, things happen out of order.
besides this, in terms of basic power, core power is only part of the equation. snap (force transfer) dominates all of it. you can have relatively low core power but if you can transfer all of that to the disc via snap, you will get a surprising result. if you have 80%+ snap efficiency you'll find you don't need much to get something going. e.g. a 10 degree rotation of the core done at a very slow speed can still put 300' of power on a disc.
if you want to compare apples to apples, you have to do something with similar behavior of the torso/hips and footwork that increases the potential power of those.
if someone like masterbeato does:
1-step throw - he can still go like 425' at will
x-step throw - he can go like 525' at will
360-turnaround throw - he can go like 550' at will.
x-step vs. 1 step yields a 19% increase in distance.
360 vs. x-step yields a 4.5% increase in distance (but like a 100% increase in calories used to perform said action)
Overall beto throws with 75-95% snap efficiency depending upon the day.
taking things on a more normal level, my wingspan is roughly 1' shorter than his and my hands are significantly smaller (less grip leverage).
on a good day i throw with ~90% snap efficiency (there's barely any way to "get more" on it for what I put in).
on those days i can:
1-step a roc 325'
x-step a roc 350-360'
i get a whopping 7-10% increase in distance by increasing the amount of core power used.
so... with that in mind, how much power do people think they can add by trying to exaggerate core motions?
granted, the worse your snap efficiency, the more core motions will influence your throwing distance, but it seems more beneficial to work on snap efficiency in those cases before worrying about core motions.
for someone with poor snap efficiency they might see something like this:
1-step - 200'
x-step - 375'.
In these cases it's a 47% increase in distance but their input/output ratio stays the same.