Twilight Retro 5K race report

Background:
I am still trying to tweak my formula to take the optimal amount of taurine to finally slow down my adrenal gland. On my last quality workout on Wednesday, I was awful but Saturday night, I was sensational on a pleasant Alabama evening (temps in the low 80s with relatively low humidity).
I still felt "a little off" when I woke up but after a mid afternoon nap, I was ready to roll.
Most of my friends from the Birmingham Track Club were there and it was great to see all of them.
Course:
Downhill start then relatively flat for the next 2+ miles. Mile 2.5 to 3.0 was gradually uphill so I expected to slow down here. My goal was 19:30 or about 6:15 pace so the plan was to bank time early and go out near 6, stay on target and be at 12:15 at 2 miles then push the hill hard and expect my kick to be strong as usual.
Race: Good start downhill. I tend to start too fast in the shorter distances but today's early pace was near perfect. I was out at 1:24 in the first quarter mile but considering the downhill start, I kept my effort even. Every time I looked at my GPS, I was in the 5:50s until late in the first mile. At the halfway point, I was unofficially under 9:30 on pace for a PR and a sub 19. I was chasing a guy for most of the second mile who appeared to be about my age. Lactic acid was building but I managed to keep a respectable pace (around 6:20) I finally caught him just after the second mile marker and continued driving toward the line. Finally, we got to the hill and my effort was good. I knew that sub-19 had slipped away but I thought I had 19:30 in the bag. Perhaps, I unconsciously let up just a tad. In any event, only one man passed me going up the hill. When we passed the 3rd mile marker, I was not pleased with how much my pace had slowed but I came back strong with my finishing kick and caught a fading runner just before the finish line. My time was 19:27, second best time ever and a 21 second improvement over my previous best of the year. Fastest time since '98 and just 14 seconds away from a PR.
Splits:
5:58 (downhill start)
6:14 (relatively flat)
6:39 (uphill)
:36 for last .11 (5:33 pace)
19:27- very pleased with that time. I think I've got a shot at breaking 19 this Fall.