Digital BW, The Print

If anyone is making excellent black and white prints from grayscale files on 
the Epson 2200, could you please share your workflow and printer settings? 
My experience is that the printer produces a short tonal scale using black ink 
only at 1440dpi (2880dpi is very slow), and the printer produces a magenta 
color cast using an rgb workflow (whether converting the grayscale file to rgb 
or leaving it as grayscale) with the color inks. I've inserted an adjustment layer 
to add green to the image as a 'fudge factor' to get a neutral color to the print, 
but this doesn't seem to be much of an advantage over the 6-color printers. So 
what is the advantage of the 2200 for black and white printing? Does it use 
both black inks when printing using 'black ink only'?