As you know, there's pros and cons to everything. Just a matter of which cons you can live with for said period of time. Using your pool as the chilling water is a great idea. Makes me want to come up with something I could use. Nevertheless, any chiller will be limited to how far it can cool your wort. If the pool is 90 degrees then.........for me, 10 mins of chilling vs 16 mins of chilling is a bit moot. I mean, how much time does it take to clean the other chillers on the backside? Clear a clog? You also have to think about cleaning and using the bag for hops because of said chiller. No one ever puts that into the equation, just the chilling times. Cleaning my IC is literally 10 seconds. I just rinse it off. It's always seemed to be a wash in my mind.
When I built my chiller I made it so the the connections are outside the kettle. I also used compression fittings and have never had a leak. Of course, I handle my stuff pretty gentle. I'm the methodical type.
For you, maybe slightly larger tubing like 1/2" might be beneficial. Since you have more wort to cool, the water will pickup more heat during its journey in the chiller. You have the benefit of being able to pump as fast as you want through the chiller since its pool water. No waste. Even save you money in the winter. Depending on if you heat the pool or not. Haha.
That's a cool pic by the way. Made me smile.:fro: it's also nice to hear my presence isn't off putting.