This thread is so epic.
outsiderunner, I wish you sincerely the best of luck in your running and training. My only recommendation is to try and accept/implement some of the advice given here.
18 months ago I started a thread that was quite negative where I lamented about my "poor" results, notably the inability to convert shorter race times into a good marathon.
Oh man I got lit on fire on that thread. Called fat (too many lb for a runner my height), too lazy (not enough miles), not dedicated, you name it.
It was tough but I saved the thread, implemented the most common suggestions. It took a lot of discipline and faith. I ran many, many slow miles (think 9:00 to even 10:00 min/mi) training for sub 3. I thought it was ridiculous for me to even think I could be in sub 3 shape despite ALMOST NEVER running faster than 8:00 min/mi (except on long runs which included some M-pace).
But I did all the work, for months, patiently, and just broke 3 this past weekend running a 1 minute negative split and 20 min PR.
It didn't happen out of the blue. It happened because I listened. It hurt my pride to reach such negative comments on letsrun ("perhaps you should forget about the marathon"), but I said "f it you know what let me change my way of thinking and give this a try".
You remind me of myself. You're stubborn and think you have all the answers. You're defensive. I am too. I too think I know it all. But sometimes, it pays to stop talking and just take all the advice in. Not all of it makes sense or is necessary, but take out the noise, and keep the good stuff. It will make you better, stronger, and faster.
Be patient and smart, and you will destroy the 3hr mark. I wish you the very, very best. You love running like I do, with a manic tendency we call "dedication"!