[FM3]

I understand that's the theoretical advantage, but I don't know if it produces any tangible differences for normal driving conditions.

They don't.

And drilled rotors can crack easier.
And slotted rotors can wear down the pads more.

 

[FM3]

If you guys can come up with more than one dumb website saying brake pad material transfers/bonds to rotors/drums I may believe you. But for now and from my long term experience, its b.s.

Doesn't that happen during "bedding the brakes" and is listed as the proper break-in on practically every website about brakes?

Bedding in your brakes is just an industry term to explain breaking in your new brakes. Bedding in your brakes helps transfer an even layer of brake pad material onto the brake rotor which assists in smoother brake operation and improved braking power.