Thanks for the thoughts everyone.

djmsbr: What do you mean by racing 3x training?

Due to work (which has changed completely for the better) I had been massively undertrained for every IM I've done in the past. Each of the last three years I've focused on specific parts. Swim/bike in 2016, bike in 2017 and now run this year. In the past I had focused on higher intensity biking and running (with much more biking than running) such that my average weekly run duration was about 2.25-2.5 hours during the IM build. Coupled with it was my terrible sense of running based on how I felt coming out of T2 and disaster has seemed to strike. My run has always been my weakness so I've worked on it by (wait for it) biking more which seems intuitive if you are a stubborn dumb as like me ;) This year I've really focused on running and it has already made a huge difference.

For goals, I am shooting for low 11s and maybe high 10s. Swim should be around 1:03-1:05. For biking my w/kg at race day will be close to 3.85-3.92 w/kg depending on whether I get to my race weight which should get me a conservative 5:30-40 bike split at LP. I'm hoping to get the marathon at 4 hrs (I did 4:13 in 2013 on the same crappy volume of 2.5 hrs per week running. I split the first 1/2 @ 8:39 and the 2nd 1/2 @ 10:39 pace which leads to the Stryd usage).

I am 45 with no history of injury. I've gone with something very similar to the BarryP style though not exactly (based on Jim Vance's book). I have some higher intensity runs which consist of a total of 15-20' once per week. I use the Stryd mainly as a governor of my activity so that I can pace hills better and begin to associate my RPE with course conditions better as I have proven to myself that I cannot race purely on rpe d/t my unconscious need to sabotage myself.

Last week (which is typical for the pattern):
Mon: Recovery Run 30' (z1) or rest, if needed
Tues: brick 20' (z1-2)
Wed: tempo 45' total, 30' (z1-2) then 15' (z3)
Thurs: Brick 20' (z1-2)
Fri: 35' z3
Sat: missed run (supposed to be 30' z1-2) after bike
Sun: 1h40m z2 (eventually build to 18-19 miles)
Total 4h10m

I also ride 3x/week (SSB, IM pace-long ride, Threshold vs EZ depending on fatigue) and swim 2-3x.

This will slowly increase in duration (with the same ratio) to a little over 5 hour over the next 8-10 weeks as I do a 2 week build and 1 week recovery since my body can't seem to tolerate a 4 week block without letting me know it. I'm not sure that I can recover fast enough to do two long runs and still get the threshold and SSB mid week rides done effectively.

thanks again for everyone's input!!!