I did my first duathlon on my Specialized Globe Sport Hybrid, which is a great bike for touring but really isn't built for speed. My overall time for the 3.2km run, 17km cycle and repeat of the 3.2km run was 1:36:12. On Friday, I got my brand new road bike, a Lapierre Audacio 400, and today I did the second in the race series, same course for the run and bike. My time?
While I did better in the run, the most significant difference was in the bike time: 51:53 last time, today that was down to 39:45. I also shaved time off my transitions, but not much more than 30 seconds overall. So while I agree you can't not train and expect to do well just because you're on a good bike, I now also think the right equipment makes a big difference. Race times for everyone in the race can be found here if you're interested, I placed 123rd out of 132 entries.
Yes, I am over the moon, and yes, this is a bragging about my new bike and my greatly improved race time post disguised as a remark on equipment. The equipment remark is still valid though, it was probably the biggest lesson for today.