My battery charge would drop quickly, and I went from one charge every two days to two charges each day without significant change in my usage. Moreover, my battery charge was frequently "lying" to me, suggesting there was more than there was or dropping quickly to 20% and staying there for longer than was accurate, so I couldn't trust the information. Multiple times, when the phone would shut itself off, I wasn't able to get it back on after charging for multiple hours, even overnight. It would appear to not be charging and then suddenly be at 100%.
The repair went smoothly. I watched the video once, but it was the step-by-step guide that I followed while I was working, especially the comments from other users of the guide. Their experiences and suggestions were valuable. The only hiccup was when I broke the second adhesive strip, but the provided tweezers were small enough to get under the battery. It took several long minutes, but I was able to gather enough of the adhesive to finish pulling it, without resorting to the heating option.
The best comment I found and followed was to remove the vibrator. That should be an official part of the guide, as it helped me to pull the adhesive strips out at a lower angle, and it would've been nearly impossible to recover the broken strip with the tweezers if the vibrator had been in place.