You have to remember that there are lots of different types of sprints and each is going to require different attributes and skills.
In small club races you will be sprinting against just a handful of people, somtimes just one or two. These sprints will generally start from a very low speed and whoever gets a good jump at the right time will usually win. In the words of Tim Krabbe in "the rider" - "Jump as late as you can but before everyone else", is the general rule of thumb. These sprints are about having the balls to wait and being in the right gear when you go.
Sprints with 5-10 people can be either fast or slow starting. Generally these are tricky sprints if they start slow as you have a lot of chance in getting boxed in and these are usually pretty messy. No one wants to lead everyone else out so you generally get a bit of stuffing around in the last few K's. They can be fast sprints if there is an attack from a non sprinter int he last 1500meters and this leads to counter attacks and a really fast run in. These are the ones where your motor pacing and positioning comes into play. Generally following the right wheel into the last 500meters is the trick here and taking note of the wind etc. To many people go early when there is a head or head/crosswind. You want to leave it as late as possible in these situations and hopefully wait for the bloke in front to open it up for you. and then just come off their wheel in the last 100meters.
Big bunch sprints are generally pretty rare for most people. For one unless you are on a closed circuit you are not going to have a whole road to play with. To be honest, these can be a bit of a lotery and often come down to a bit of luck and who is preparred to tak the most risks. Being assertive enough to hold your position and going with what your insticts tell you is generally the go here. Most of us will not have a HTC leadout train and so big sprints are a bit of a dogs breakfast with people going everywhere.
The bottom line is you have to train for the races that you are most likley to participate in. I would fully support the contention that saving energy buy being able to corner and follow wheels well should be a priority. Next is to get good at two or three up sprints, which the drills I outlined earlier will really help. last is to practive sprinting as much as you can.