pike51 I think the biggest thing about pace of play is a lack of understanding about how to play "ready golf". Too often I watch groups where players don't get themselves ready while another player is hitting. There is nothing stopping you from getting your yardage, grabbing your club, and getting ready to hit while your partner(s) are doing the same. Often times, when we stop the cart for the first ball, myself or my cart partner will jump out with the rangefinder and walk to the other ball (with a club or 2) and be ready to hit. Then, once the first player hits, they can hit and everything moves along quickly. It's not even about preshit routines or practice swings that slow things down.
Totally agree with this - if you have to wait (for the group ahead, or for someone else to play a shot), use that time to get ready to play your shot. Most of the time, you'll be able to get a distance, work out what the wind is doing, think about the type of shot you want to play, read the green, or anything else to prepare while you're waiting.
One trick that I'll use if I'm not able to stand by my ball while I'm waiting is to get a yardage using my rangefinder and work out the difference to the yardage on my GPS watch - I can then get a reasonably accurate yardage to the flag when I get to my ball with a quick look at my watch and applying the difference, with no need to zap the yardage at my ball.
(That's something that I remember noticing when I was marshalling at the Scottish Open over the last couple of years - there were a few players who would only start to think about their shot when it was their turn to play, even though they've been waiting for several minutes for the group ahead to move out of range. Yes, these guys are playing for a lot of money (and for their careers in some cases), but there's still no excuse for using the time that's available to you.)
Regarding marking the score - the guys that I play with most weekends usually have one scorekeeper per group of 3 or 4 (I usually do this for the group I'm in). I'll mark the card on the next tee before I hit my shot unless I'm up first - done right, it doesn't get in the way of keeping play moving.