Jerry, all of my wiring is stranded and all of it is wrapped around the terminal screws at all outlets and switches! Is this wrong?
While I'm neutral on the subject of stranded thhn in conduit vs. solid romex and tinned boat wire (I believe they are all safe if installed properly), I have to go with Jerry on this one. Wrapping stranded wire around the switch and outlet screws is just not safe. There is just too much risk of the connections becomming loose or the strands breaking due to vibration or overtightening of the screws.
I highly recommend you go to waytekwire.com and order a bunch of crimp on fork terminals (I'd recommend ring terminals, but often the screws in switches and outlets are designed so they won't come out of the holes) and a good quality crimper such as their number 434. http://order.waytekwire.com/IMAGES/M37/catalog/218_027.PDF At $131 it's not cheap, but it's the best money I've spent on bus related tools, so far.
While you're there, get yourself a good stripper (no, not that kind) such as their item 444. Again, money well spent in terms of quality of the end product and time spent.
They also offer some clear plastic shrink tube which can be used to attach paper labels to your wires while insulating crimped terminal ends.