Marathon countdown: 10 weeks to go

This is the time I start getting a little anxious. My marathon, the White Rock Lake Marathon in Dallas, is in 70 days. Here is what's going on inside my head right now:

*Have I run enough mileage? In the last 30 days, I've run 188 miles. That's about 44 miles a week for the last four weeks. Even though I haven't tapered and even though I've got 10 more weeks to get build up to 50-mile weeks, I go through all kinds of crazy formulas in my head about how fast I could run the marathon if it were next week. One formula I've heard of is that you multiply your average daily mileage by three and the number you come up with is the distance you could safely race your hardest.
The formula implies that to race, RACE, a marathon, you'd have to average 9 miles a day (9x3=27)
So, in my last month, I've run 6.28 miles a day on average. Multiplied by 3, that is a race of 18.83 miles. So what does that mean? Should I run slow for the first 8 miles of the marathon, then try running marathon pace the last 18 miles?

I've also read that to figure out your marathon time, you should multiply your 10k time by a ratio that depends on how many miles a week you run. The ratio, which I am lifting from Jim2s running page, goes like this...

30-35mpw: 5.5

40mpw: 5.0-5.3

55 mpw: 4.9

60 mpw: 4.75-4.85

70 mpw: 4.70-4.80

80-100 mpw: 4.55-4.65

What this means: If you average 40 miles a week in the 16 weeks before you taper, you multiply your 10k time (in minutes) by 5.0. If you are running 60 miles a week in the weeks before you taper, you multiply your 10k time by 4.75.

The premise that your marathon time is based on your natural speed and the volume of your training. If you are running 30 miles a week and you your 10k is 50 minutes, this formula says you'd run a marathon in 4:35.

Me? I'll need to run a 10k soon to test my fitness, but I think I could run one in 45 minutes. Multiplying 45 minutes by 5 (ratio for running 45 miles a week) would put my marathon time at 3:45, or a pace of 8:35 a mile.

Having run a 7:50 minute/mile pace during a 20k two weeks ago, I definitely think I can hold 8:35 for 26.2 miles.

And still, I fret...

I ask questions of other runners about how many weekly miles they run compared to their best marathon times, and those answers don't give me any more insight into what I might do. I know several runners faster than me who've yet to hit 50 miles in training. And so, what this reminds me of is the fact that marathon training is. ...

AN. EXPERIMENT. OF. ONE.

I can read all the marathon blogs I want or ask people all kinds of questions and when I toe the line on Dec. 14, none of that will matter. It'll be about my training. My tapering. My body.

And still that won't stop me from fretting.

My week: Going to run 46 miles (I ran 42 miles last week, 44 the week before). It'll break down like this:

Today: 5 mile recovery run (did it in 9:22 pace)
Monday: off
Tuesday: 7 miles (1.5 mile warm up, 4 in 7:30 as a tempo run, 1.5 mile cool down)
Wednesday: 8 miles with 4x.20 mile hill repeats in the middle
Thursday: 6 miles easy
Friday: off
Saturday: 20 miles (did 18.25 two weeks ago)