As I suggested in replying to your other thread on the same subject, your reasoning is plausible to a degree but you have failed to take into account other important design issues. I can assure you that printer manufacturers invest a lot of time and money into research to deliver a product that is reliable and technically advanced and the design of inks and print heads is far from as simplistic as you make out.

So, if you have put dyes into your pigment ink printer and find that it no longer works, you might have also discovered that the two ink types may not even mix and interact giving a fluid of even different characteristics if you did not flush out the entire system beforehand. Perhaps a knowledge of the chemistry of the ink types might help as well.

I somehow suspect that you seem to be blaming the manufacturers for your misuse of their product. I've no idea what your objectives and motivations were in doing this but if you were advised to do this by a supplier, I would suggest that you complain to the supplier rather than doubt the technology itself.