PR!!!! PR!!!! PR!!!!

In 2 hours 21 minutes and 32 seconds I ran the Los Angeles 13.1 half marathon...a personal record!! Not just a PR, but a I totally crushed my previous best by almost 20 minutes!!!As the official test race for the LA Marathon, this was better than I could have imagined...but it started the questions flowing...
--If I could cut 20 minutes off of my half marathon time could I cut 30-40 minutes off of my marathon time?
--My training runs haven't really shown this huge increase, so where did this come from?
--For the first time ever I ran with a pacer (the 2:15 pacer) for part of the race, was this the reason for my improved time?
--For most races I have tried to run negative splits (increased pace in each progressive mile) in all of my previous races, but since I ran with a 2:15 pacer for the first 6 miles, should I scrap that?

So many questions...there will be plenty of time to contemplate them later...but for now I'll just take some time to enjoy my new personal record!! 2:21:32!!! Whooo-hoooo!!!!