I think a main problem of mine is definitely the extra 6 to 7 pounds I have now over last Aug. That's my top priority.
But I did again make some error. Last time I ran 21:05, I used the virtual partner function of my Garmin 205. In the 3rd mile, it became a bit irratic and I lost focus.
This time, I used lap pace to set my pace. The lap pace of my 1st mile, before I hit the 1st mile marker was showing up at 6:46. I thought I am on track to get close to my PR. Well, when I hit the 1st mile marker, actual lap time was 6:55. Same thing happen for lap 2. By lap 3, I already knew I was out of it. Well, I might be able to get 5 to 10 sec back had I known but I would still be a lot slower than my last PR.
The good thing is that I know I need to aim about 9 to 10 sec faster when I use Garmin 205 lap pace next time on this course. Most other courses I ran with 205 was ok except this one.
I might be relying on GPS too much, but had I not, I would have run with some of the folks at 6:15 pace in the 1st half mile. I slowed down after the 1st 0.1 mile or so and caught most of them by 1/2 mile or so. So, technology did help me a bit.