The knowledge that if I go to sleep, it will take me hours to get back in the zone again.

Try limiting your naps to 20 minutes. This prevents you from entering the deep phases of the sleep cycle which is what causes you to be drowsy.

If you are really hardcore you can go all out and convert to the Uberman polyphasic sleep cycle. 6 20 min naps, every 4 hours apart. Once adapted you can code for 22 hours a day its awesome...

Are you doing a true uberman schedule? How's that working for you?

Right now I have a core sleep of about 4hrs each night. I had to come off uberman when I started working as I cant really take naps at the office except for lunch. All the more reason to quit and found a startup right?

If you're really interested you should try to find a copy of Why We Nap by R. Broughton. There's a lot of confusion and general BS on the net about Polyphaic sleep. This book takes a scientific approach. The problem is its no longer in print so you might try a university library...

As far as how it works, I love it. Being awake for so much of the day is a huge plus, but the biggest improvement is actually in how you feel. Much sharper, better concentration, mood, etc. That is if you can make it past the adjustment period and you can stay on schedule. The big downside is that its still socially a "weird" thing. People will look at you crazy when you try to explain it...

I'd consider doing it but the unknown long term health effects really scare me. I did a biphasic sleep schedule when I was working an 8-4 last year. I would sleep for 3-4 hours before work, then take a "nap" for 4-5 hours after work. About once a week I would go to bed at 5PM and accidentally sleep through the night.

Are you affected by food comas?