So you are reframing the question to suit your needs. Not unexpected, so let’s revisit your original claim...Okeedokee but...
"...Does not lower the power reserve; that's a myth. No, it's not a myth. When the chrono is running, the mainspring has more work to do. Sure, it won't run down any faster, but it will reach a point where there's not enough strength left to keep the movement going..."
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"and they also lower your power reserve"
And you went on to describe this as:
"the watch will run out of power faster"
It's clear from my posts that the watch will stop sooner with the chronograph running. On that we agree, however you attribute this to it somehow using power "faster" which is completely incorrect, and actually not possible.
Again the power reserve is designed into the movement, and is based on the length of the mainspring, which in turn determines how many revolutions the barrel will make. The barrel in a Speedmaster Pro for example, turn the center wheel, and the center wheel has the cannon pinion fitted to it - the minute hand goes right on the cannon pinion. The gear ratio between the barrel teeth and the center wheel pinion determine how many revolutions of the center wheel will happen before the mainspring stops unwinding - that is the power reserve. As I've said, that doesn't change unless the length of the mainspring changes, or the ratio of the gearing changes.
The formula for this is as follows:
n2/n1 = Z1/Z2
Z1 - number of teeth in the barrel
Z2 - number of teeth in the center pinion
n1 - number of revolutions of the barrel
n2 - number of revolutions of the center pinion
This formula is from The Theory of Horology, which is the textbook used for most watchmaking schools (WOSTEP, SAWTA, etc.).
What does change is the load on the movement side, so that can be from a chronograph running, a date change mechanism, or simply lack of maintenance with dried up oils and debris or wear in the movement. But none of these things cause the spring to unwind faster, or the torque level of the spring to drop off faster, which was your original assertion. This is simply incorrect, and doing the simple test I've described above would illustrate that for you if you really wanted to understand this.
In fact a number of years ago there were a number of people here in the Omega section that did this very test, and the results were compiled into a thread. The search function on this site is so bad I haven't been able to find it, but if someone out there can find it, it would help people understand this more completely.
If you want to claim this is just a semantic argument that's fine, but there is a material difference in the two ideas that I'm not sure you fully understand (or admit to) yet.
But if you want to claim that this is still wrong somehow, and go against hundreds of years of horological knowledge, hey you be you man...