1) I disagree that Goucher is too big... he is extremely lean, and 150 is not TOO much. If anybody is carrying around extra weight it is Bob Kennedy - he has the "skinny- fat" thing going on. No muscle definition whatsoever indicates a thick subcutaneous layer of fat (thick for an elite runner, that is).
2) Heavy is not good, even if it's bone/muscle weight. There may be some good runners who are unconventionally heavy, i.e. McMullen...... but few, if ANY of them are among the best in the world, and the are still getting their asses kicked by the 125 lb. cats at the international level. Skinny and light rules, and bigger muscles are NOT an advantage