I started with Fundamentals after the first Tim Ferriss podcast and then added Foundation1/Pro at the end of June. I added H1 and the stretch series at the beginning of August. I love all the information about the "old folks" who have had success as I am 52. I started with reasonable basic fitness, but almost no mobility. Not surprising, the push up and plank type progressions have been pretty easy, but shoulders, hips, ankles, calves.... well let's just say I have a long way to go. I love the progressions and I am remembering to take the long term perspective.
My question: are there any long term issues with stretching like this? An acquaintance of mine just had hip replacement surgery at about 58. He blamed it on many years of excessive stretching for his martial arts competitions.