Yes yes, absolutely.

I have no theory at this point, only an unexpected observation. I posted here precisely to learn about the impact of saddle fitting on power measurements.

Since it'll take more than a month for me to get a replacement for the Brooks, I won't be in a position to reach anything remotely conclusive. We'll eventually see.

(just wanted to add that power meters report the pressure that is exerted on the drivetrain, irrespective of riding technique. The questions of how effective a rider's body is capable of generating X watts of pressure over some period of time, or how effectively power translates into speed are indeed important, but way beyond the scope of my observation)