[Sylvanfan]

I did under the dishwasher when I did my tile. It's really not that bad, and it's not very much work. Thats the type of thing an home inspector will rip to shreds, and will make your work stand out as amateur. You don't have to get your spacing right, and you can do a half ass job of the grout in those areas, but I'd reccommend putting the tile down. If people think it's an amateur job, you won't get as much money for your efforts.