I have very narrow shoulders, no lat development, and my tibialis anticus (in front of my shins) is way underdeveloped. I am really worried about this problem (my tibialis). My legs are so-so but I have huge thigh biceps. They are humongous. That's it, but my main problem is my tibialis.
Your problem is not your tibialis my friend. I strongly suspect from your letter that your problem is between the ears.
After admitting that your physique is "narrow shouldered, no lat development with humongous thigh biceps". Why would you be so concerned with a Mickey mouse muscle like the tibialis anticus?
Your physique sounds like a mess, but the tibialis is not your problem!
I suggest you embark on an all round routine of wide grip parallel bar dips, upright rows, lateral raise, wide grip chins, front squats (heels on 2" block) calf raise, crunches, incline dumbbell curls and triceps extensions. Five sets of eight. Split your routine in two and train three days on, one day off, doing only half the routine each workout... and for God's sake, forget the tibialis'.
(Musclemag Magazine March 1986 Vol. 11 No. 2)