1. Put a cam in close to you, clove hitch the rope to its racking biner.
2. Put another piece in a little further away, clove hitch the rope to it.
3. If you need another piece, put it in now, and clove to it.
4. Pull up rope, slap your [belay device of choice] on, and yell "On belay _"
*Climber ascends to belay, then continues to lead the next pitch. He yells down "I'm anchored _"
5. Start disassembling your anchor to whatever you feel comfortable with.
6. You hear "On belay _" from above.
7. Drop the last clove hitch or 2, rack those cam(s), and GO!
How could a cordelette be faster than that? Consider the time it takes to de-rack and re-rack a cordelette.
It takes me 2-3 seconds to whip up a clove hitch, and 1-2s to later pull it off the biner.
My 18' 7mm ACR cordelette weighs in around 300g with an ultralight locker.
That's about the same weight as 5 Metolius TCUs, or a #4 Camalot C4.
I usually still have a variety of biners, a 60cm or two, and sometimes a 120cm sling at the top; if I plan on switching the belay over, they come into play.