hi SC, nice job getting back into it, and good luck with the marathon training. As you can tell, this forum isn't nearly as active with distance running stuff as it used to be, especially four or five years ago. The good news is that if you're ever feeling unsatisfied, there are a handful of great books about distance race training in general and marathon stuff in particular, lmk if you want a few suggestions.
There are also some good online resources but maybe nothing's more consistently useful than the
McMillan Pace Calculator; obv it's not perfect across all distances for all runners but for most people it ends up being spooky accurate. Probably you use it already, but if not then there's the link.
A couple general concepts that you also probably already know:
--imo the whole Woody Allen quote about how "90% of life is just showing up" really suits marathon training. Four months of this crap is a long time and there are going to be setbacks, mostly small ones (scattered atrocious workouts, scattered low energy days, etc) and probably one or two big ones (sickness, injury, other bs). It feels like a catastrophe when it's happening, but just try to remind yourself that this stuff happens to everyone and the important thing is just not to overreact. Don't beat yourself up over a couple bad days, just keep showing up and trying not to force the issue too much.
--sure, if you want to get all your marathon goals then some of the workouts are going to be sincerely hard and you'll have to suck it up. But try to pick your spots, because for tons of people the hardest part of marathon training is resisting the temptation to always do more. One piece of running advice that you hear a lot is that "it's better to show up at the race 10% undertrained than 1% overtrained," and man this is SO TRUE, but unfortunately it seems like the kind of thing that everybody has to learn the hard way. That said, if you're ever overtraining, then my nuanced advanced advice is to ****ing knock it off. Everybody has unexpected bad days in training, but if you have three or four in a row where your energy and enthusiasm is flat (and your resting pulse is high etc), then don't be too proud to reevaluate and/or to give yourself a legitimate break. It's a gigantic pain in the ass to recover from overtraining after the fact, so do your best to not be a freaking hero all the time and find a balance.
--one of the most common mistakes that marathon runners with your background make in their everyday training is that they run their easy days at too fast a pace. If you are constantly letting your easy/regular pace creep faster and faster to where you're having to exert some actual willpower in the majority of your workouts, then it's gonna wear you down. Look at those McMillan pace charts for this stuff and trust them. And it's fine if you don't wear a pulse thingy, but do learn how to periodically take your pulse for 15 seconds and get a sense for what your ranges are.
--the most common mistake that distance runners make with their form is having too slow a turnover. Tons of smart stuff has been written about this--including in this forum and you can search for it--but the bottom line is that the next time you're humming along at, say, 7:30 pace, count how many times your left foot is hitting the ground every minute. If it's below 87ish, then you would definitely benefit from nudging it up a little, and ideally you'll bump it to 90 or the low-90s (but any higher than that and it might be counterproductive). It's a surprisingly complicated topic, but for now just trust me that if you're at 85 or something, then gradually working towards a faster cadence (while keeping your pace the same) is going to solve a lot of problems.
--the most common mistake that runners make during races is to start too fast. Yes, I know you know this already, and sorry, but it's so important that imo it really can't be repeated enough. In a 5K for example, if you go out too way fast even in just the first 60-90 seconds, you are absolutely going to pay for that later in time and suffering. In October you are going to be at the starting line for your marathon and feeling terrific, looking sharp in your lucky socks and feeling cocky because you finally took a satisfying dump in the port-a-pottie on your third try. Congratualtions, and now that everything's going your way, please do NOT be one of the ten thousand goofs who get bewitched by the pre-race adrenaline and run the first mile of their marathon at their freaking 5K pace. Man, just please don't. Instead be the one person in a hundred who makes a good plan and trusts it and keeps it.
--the Higdon stuff is fine; honestly pretty much any plan is fine as long as you're out there putting in the time. But my kneejerk reaction to Higdon's intermediate plans is that it's a little weird to not be doing any speedwork. I don't mean that you need to be doing two tempos and a VO2 workout plus strides every week or anything idiotic like that, but imo you'd benefit from striking some kind of balance here.
Sorry for the wall of text but I'm not in H&F too much and I don't know if I'll see this again anytime soon. But best of luck with everything and we're rooting for you. And definitely keep massaging the **** out of your legs, especially with your history. Some people have more luck with one of
TheSticks than with foam rollers, especially for the deep masochistic calf stuff.