Ari Auvinen, the inventor of SmartPaddle, founder of Trainesense and former competitive swimmer, shares great insights and his experiences on force measurements in an article on SimpliFaster sport science blog: https://simplifaster.com/articles/swim-faster-smartpaddle-sensor/
SmartPaddles have many advantages as a tool for analyzing and getting an objective view of the swim stroke technique, but in my opinion the greatest advantage is to get a view of what actually happens in the pull and push phases of the stroke, a part that is somewhat limited in analyzing with simply looking at video. Video PLUS force measurements is a very powerful combination. Especially since you get information on asymmetries between the arms, that might not be visible to the eye, as well as an indication of whether the proper muscle groups are being activated at the right time.
Check out the article on SimplyFaster’s blog! And if you are interested in a force measurement analysis done by a professional, don’t hesitate to contact me at email@example.com.