Power Meters / Powermeters (SRM, Powertap, Quarq, Ergomo, Vector, Stages, power2max, P2M, 4iii, InPower, Cinch)

You'll get the hang of pacing efforts as you do more. It's just the way it is. We don't 'know' what our max is over a period of time until we've done it and most likely done it a few times.

"averaged 310 watts in the warm up 5 minute effort"
That doesn't sound like a warmup unless you're doing a prologue.
Find a warmup protocol and stick to it (again, you'll nail it the more you do it)

Here's some overly complicated ones..
http://www.o2endurance.com/content/?cid=42&cat1=371&cat2=286&cat3=0&level=2&id=286

As it turns out, 133% of my FTP. Although I was expecting a higher score. Something that would have put it at 110% (280 watts).

You are a year older than me.

Feck. Thats that excuse out.