Digital BW, The Print

Every time I switch between my color cartridge set an my B+W cart set, the printer goes on a head cleaning frenzy that takes at least five minutes to complete. I really don't know what it is doing during the period, but I suspect it is using quite a bit of ink for nothing. I shoud mention that it really does this every time it goes to the head park position. It will do it after just replacing a single cart as well. 

It this process necessary? Is there any any way to prevent it from doing this? If I had the space, I'd be tempted to grab one of those new 1430 printers just so I could have two: one for color and one for B+W. 

BTW, I have no other issues in switching cartridge sets. I usually print a nozzle check page (those print quickly!) and if it is good (it usually is) go ahead and start printing. No cleaning, flushing or printing of purge pages is necessary.