The assumption that dirty dishes get collected in the sink alwas confused me, too. You have to take them out before you can start work, and you can't use the sink well while they're in there, so it seems very impractical. Do you just pour water on the collected dishes?

Here's how I do the dishes:
- I collect the dirty ones NEXT TO the sink.
- I put warm water with dishsoap in the sink.
- I clean dishes in that water until the drying rack is full, or the water is too icky to clean anything (though then I might give something like a fatty pan a first pass so I can clean it properly later)

How do you do the dishes that cleaning just one seems practical?