Vern Gambetta is one of those people. I attended one of his clinics in 1998 and consider him one of the best in the strength and conditioning business. He pulls no punches, tells it like it is, utilizes methods from sport science and rehab science, and (my favorite)whores himself out to nary an equipment company.
Vern has a great blog, Functional Path Training, and I recommend it to anyone in the strength and conditioning biz. Nice to see someone with a great reputation taking the time to comment on current topics. Check out Vern's latest post on the machine vs. free weight debate here.