Are there are any who believe in a barefoot doctrine approach to treating foot pain?

Yes: If you mean barefoot running the answer is yes.

Separate the two: If yoyu want to barefoot excercise or run - fine you can, as long as it does not cauase you cany pain. However, when you ask to 'treat pain".....First find out what is painful , treat it and then train as you wish. Hope that answered your question.

Be Mindful: Long term effects of barefoot running is not well documented. High impact on a hard surface can displace and damage the fat pad, which thins naturally as we age. By causing high impact repetitive trauma on weight bearing areas of the foot can have long term complications. Podiatrist see this in daily practice with out many treatment options available currently.