On my boat, it's the balance of the sails and the mechanics that will allow the WP to do the job, or not. If you have too much helm(unavoidable in some conditions), that will overwhelm the power of the WP.

And then in some conditions, if you're turning the wheel quickly in anticipation of an erratic seaway, the speed of the WP is only so fast. An under deck can have more power and speed, but there are no mechanical miracles for some conditions.

I've had several people with smaller boats tell me they could not get a WP to work for them. I'm not surprised, they're not a strapping 250 pound helmsmen with experience(no AP can compete there).

Those conditions that make an AP work overtime are also tough to sail or at times uncomfortable for crew so I'm pretty much in agreement with the WP, and make changes.