Allow me to return to the subject of Black Point Compensation, if only to test my understanding of the subject (which may or may not be fully accurate). Comments and corrections gladly received.
The last sentence of this quote puzzled me. The ultimate aim of BPC is just as stated in the RawPedia to ensure that the blackest black in your image will match the blackest black your printer-paper combination is capable of reproducing,
This is accomplished during soft proofing by using the ICC profile supplied by the printer for the printer-paper combination to be used. Checking the BPC box in the ICM panel for soft proofing ensures that the image on my monitor accurately reflects the deepest black of the image when printed.
Whether or not this compensation is used for the output image is immaterial and will depend on the output profile in effect when the image is saved/exported. I write “immaterial” because the print shop will print the image they receive (using the ICC profile which they provided) without regard for whether or not I used BPC when soft-proofing the image prior to sending it to them. (i.e the print shop does not “use” BCP; that’s left to me.)
If the foregoing is correct, it explains my confusion about your remark