OK, I know what I think my goal time should be but I'd like to get some input from you guys.  My log is open if you want to have a look at that, feel free.

Assuming perfect weather conditions and I'm having a great day (big assumptions, I know) I have three goals in mind.

A: 3:55

B: 4:00

C: 3:50 if I lose my mind.

ETA: I didn't mean to this quite yet. I thought I backed out but I must have clicked the button by mistake.

My plan is to line up with the 3:55 pacer and run with them for at least a few miles but probably for the entire first half of the race. From there I will evaluate how I feel and decide if I want to try to pick up the pace just a little or stay with them.  This is of course based on the assumption that the pacer is running even splits.  I know it would have to be an exceptional day to make up 5 minutes in 13 miles so I doubt I'll hit 3:50 but if it feels right that's what I'm going to shoot for.

I'm thinking A or C in perfect conditions.  Don't stop on Rock Creek to do pull ups on the equipment and you'll be golden. 

Scott, there is no doubt you are going to get yourself a HUGE PR!

I too think A is the way to go.  Your tempo run this morning suggests that your fitness is better now than it was at the time of your half in the fall.  I wouldn't be surprised if you end up picking it up in the second half and and coming in around 3:53.  But going out at 3:55 pace still leaves you with a nice 5 min cushion to break 4 hours in case you start to run out of gas.