The more I read the more I think this is almost the normal condition, but may be dirt one one of the senders. Is there anything that can wear? Not bushings on this car. To the guy switching rotors - this is exactly what it seems like at first, but when you switched rotors did it go away for a time and then come back? What did the old rotors look like?
It's just not possible to go through rotors like that unless the pulseing is so bad as to wear them very quickly. I think it all relates to the sender causeing the pump to act badly. This is not so apparent under hard, high speed braking - right - more in just normal stop and go traffic?

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89 300E
79 240D
72 Westy
63 Bug sunroof
85 Jeep CJ7
86 Chevy 6.2l diesel PU

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