Thanks for the continued suggestions!
Quick progress update: tried yet another trainer and puppy has greatly improved his responsiveness while in a pinch collar. He is now cooperative enough to go on my morning run and mostly stay in "heel" position; still some pulling excitment when passing fenced barking dogs, but the lunging/barking/chaos is greatly improving. Took him to the barn this weekend and he spent some time playing (while leashed) with two other dogs. Still a long way to go, but huge improvements.
ETA: If he is ever "socialized" enough where off-leash play is tolerable, he'll get to spend his weekdays at the 10 acre ranch I original planned to use when we first were considering adding a dog to the family. Until then, our little morning runs are wearing him out enough that he's enjoyable to be around the rest of the day.
Last edited by Cynical25; 05-09-2013 at 02:23 PM.