Honestly, I get where you’re coming from with the “kick the can” thing, but I’ve actually had decent luck with lining—at least for a few years at a time. Maybe it’s just my setup, but after lining a stretch under my driveway, the roots didn’t come back as fast as I expected. Could be luck, or maybe the trees in my yard are lazier than most.
Copper sulfate always made me nervous. I tried it once and my dog wouldn’t go near that patch of grass for months. Plus, I kept wondering if it was messing with the rest of my yard. These days I stick to mechanical cleaning and root barriers if I can swing it. Not perfect, but less drama.
Full replacement is rough, no argument there. But sometimes patching feels like putting duct tape on a leaky boat—works until it doesn’t. Guess it just depends how much hassle you’re willing to put up with before biting the bullet.