In reply to mountainbagger:
A few things that have helped me with tapering:
I do my last long run 3 weeks out then a gentle taper, including a 3 hour run 2 weeks before, a 90 min run 2 weeks before and lots of 1 hour or 40 min runs in between. The thing that really helped me was to run the same amount of times I.e. 5 or 6 days per week, but for shorter durations and low intensity (no hill sessions or pace sessions)
For me, A steeper taper 3 weeks out causes the taper tantrums (I like this new phrase!) And I often come down with a cold
Sports massage is v helpful as is self massage but strictly light pressure only in the week before
Carb or any other food loading does not work for me, it is more important to have practiced food intake during training runs
Swapping runs for walks with friends during tapering is a great way of reducing intensity and catching up with friends who you have neglected during training
Low intensity runs in the last few weeks are a great chance to test kit, practice kit faff etc I have practised mid run foot taping, torch battery changing, re finding the route after being lost, jogging while carrying cups of tea, walking while eating a bacon roll and all sorts of other random things, very helpful when I have needed to do these things on a race
Pacing : not sure on this one as has previously been mentioned, so much depends on terrain, weather etc. If there are cut offs, be aware of what average speed you should be going, and how each section may be re speed. For long ultras I make myself a laminated card with increasingly slow average times per section and an overall average with a best case, most likely case and will just pass cut-offs speed. V helpful to refer to when knackered 15 hours in.
Good luck; what race are you doing?