Have a look at this article about male German soldiers accidentally growing breast due to the repetitive slapping of their rifles against their chests.
http://jezebel.com/5978289/male-german-soldiers-are-growing-breasts
This would indicate that Thai breast slapping does have merit to it.
http://www.odditycentral.com/news/breast-slapping-a-thai-beauticians-alternative-to-plastic-surgery.html
http://jezebel.com/5978289/male-german-soldiers-are-growing-breasts
This would indicate that Thai breast slapping does have merit to it.
http://www.odditycentral.com/news/breast-slapping-a-thai-beauticians-alternative-to-plastic-surgery.html