Has anyone successfully merged a HIM and Marathon Training Plan?

I have basically taken my planned training for the year from several sources and created my own training plan.  I have a half in July, a sprint in August, an Oly in September and a Marathon in January.  For the marathon I am planning on using the Pfitzinger 18/55 plan as well.  I used the import/export feature to get the blank template, spent a couple of hours entering the data and then imported into my training log.  You can find the instructions for doing it here. 

I trained for both a HIM and marathon last year. I did the Longhorn IM 70.3 and then three weeks later I did the Marine Corps Marathon. Longhorn was my "A" race while the MCM was my fun race. I ended up with a PR (3:37) at MCM. I realized that I could PR at around the 18th mile mark when I didn't feel as tired as normally do.

The only thing that I did that was different from my normal standalone HIM training was that my long run weekends were at a marathon level distance versus a HIM level. For example, I don't run anything over 12 miles while training for a standalone HIM whereas my marathon level runs had me going 22 miles as my longest run. I also probably ran 1-2 days less per week than when I just trained for a marathon only. The bike and swim were done at the same distance and level of intensity as a HIM only plan.  I was still biking and swiming even after the HIM was over.

My training plans are self-made.  It has no name

All great stuff.  After reading everying from this thread, and the Georgia thread, I think I'm just going to try an maintain my 20+mpw (like I am now) and get it up to 25 mpw between E-man and R.I.  and then after I am fully recovered from R.I. I am just going to do a "Run Focus" and follow a Pfitz plan using biking and swimming as Recovery.  I'm thinking maybe I can get all of my running done in the morning, and with ever is left over swim at lunch and bike in the evenings.  Oh man, this is going to be fun.

Last year I developed ITBS because after my HIM in October (averaging 20mpw) I went right to 30+ mpw trying to get ready for Philly.  This year I plan to increase my volume a lot slower -  10 to 15% per week.