Thanks for the comments. Appreciate them.
I myself was baffled with some other happenings when I played that day. There was something wrong with the numbers when I realized some other things. On that day, I realized my Starmie was slower than an Adamant Flygon, my Roserade died to special attacks it shouldn't die to, and Swampert dying a lot faster than usual.
I checked back to edit the team and realized my nephew had messed up with the figures on my IVs, natures, and EVs on most of my teams, as he played shoddy on my computer the day before. I had to readjust them. I have no idea why my nephew would do this though. -_-
So, I'm sorry if the log didn't represent an actual scenario of how Gyro Ball's damage to the water-types. Now this war story isn't as good anymore. I don't like it anymore :-(