I use almost this exact same workflow. I shoot on a pentax 6,7 scan with an Epson 4990, and then print with a hp9180. The reason I do it is the very different depth of field characteristics that larger format cameras give you, the far greater tonal range of black and white film coupled with the repeatabilty of printing a digital file with an inkjet printer. This is a very labour intensive process, because of the scanning and dust spotting but for black and white gives you the best compromise between film and digital processes.