Why even use Handbrake and not just turn saturation on your TV/display to zero? Seems much faster solution and you can decide whether you wanna color or B&W option with same video file.
I'm a data-hoarding AV nerd who keeps hand-rips on a big NAS anyway, wasn't exactly out of my way :) I now have both the color and B&W versions on tap with the rest of the collection.
that's hour or two longer than it takes to adjust saturation to 0 on display device, even just setting up encoding software takes longer, so it's waste of time
what's the benefit of doing this? you waste your time and you lose color option, I see no advantages over just adjusting saturation
