That was informative, thanks.
Yes, I got stronger than ever in my life through Starting Strength. For me, someone who had never really done any kind of serious weight lifting, the gains seemed impossible. Being at a certified gym was very useful because you could watch others do the work while you were resting and learn from the corrections and advise they were receiving from the coaches. It was also very useful because being told you could actually lift the weight you just failed to move off the ground meant you didn't quit --something that can easily happen on your own if you don't know what you are doing. This is where I learned just how much of "I can't move this" is actually in your head.
The other thing it did for me is remove the pain and the barriers of the many failed attempts over the years. I just didn't know what I was doing. Lifting just 150 lbs off the ground without any notion of proper technique was at times painful and impossible. That's how I ended-up at a Starting Strength gym.
And yet, just as you mention in your note, I was getting fat. I was stronger than 99% of the people I came into contact with on a daily basis (including at my regular gym) and yet, I was putting on fat. This is why I walked away. The coach kept telling me that we would start addressing that once we got to a high enough plateau of strength. I wasn't comfortable with continuing along that trajectory.
My thinking at the time was to slim down and restart from a better BMI. I had a less-than-ideal BMI when I started. I don't think this helped. I also needed to learn how to eat better. Your dietary needs change with age and we don't always make optimal adjustments. Aside from that, a change of focus to a balance between a moderate strength gain slope and healthy body metrics seemed like a better idea.
I am now about 10 lbs from where I want to be to restart. I hope to get there within the next three months. Diet only, no heavy exercise at all other than some walks and going rowing a couple of times a month. I needed to understand how to modulate body metrics with food rather than insane exercise regimes that are simply not sustainable in the long run.