Here's all the formula you need: BEL = Fast
Good stuff Lee. I totally agree. I'm a young buck in my 40's and I don't think I'd want to line up against you. I've only been racing cx for three years but each year I age (and gain experience), I am 100% certain my current self would beat the previous (younger) versions of me racing. Heck, I'd even take me now in a race vs when I was 25. I also focused on diet this year - close to the 40/30/30 diet you mentioned and it's working. I'm dropping weight, have more energy, and hopefully that will make me faster. Hoping the best for you this season and at Worlds.
Throw out all the variables (where your live, experience, race conditions) and boil it down to a simple yes or no - should you run - and the answer is emphatically yes. Combine with the bike ride or after a warm-up then mimic your race efforts. Sprints or repeats up hills/steps will do wonders for you in a race and perhaps give you an advantage to gap your competition at critical moments when your feet are on the ground instead of on the pedals.