I suspect that it was this article which was the subject of a very similar thread last fall. I'm happy to see a more reserved not jumping on the bandwagon this time. As said, if well planned, and carefully executed, above a certain not published altitude, it can be done. I practiced it for hours, at a quiet runway with lots of options. The result of all of this practice was my forming the opinion that if for real, I would never consider it below 700 feet in a C 150, and even that, if I had planned my takeoff to accommodate it.
A friend of mine with more that 23000 hours had his homebuilt quit over the water 300 feet up after takeoff. He splashed it, and we got he and the plane back. Last year, different homebuilt, quit in the same place, he turned back, we got neither back.
You can develop a lot of drag really quickly in a turn. While test flying a Caravan with a draggy modification, I was practicing glides from the ideal spot in the downwind, and had trouble making it without adding some power.
My feeling about turn backs is similar to aerobatics, and a few other advanced maneuvers: If you have to ask if you can or should attempt it - you should not.