The reason I was thinking that my blade was different was because of how worn out it is. Even though I sharpen it regularly, it has worn down in the 7 years of use. Yes, I am still on the original blade from 2007. It isn't square anymore. 7 years of sharpening it have caused the "blade" areas to be recessed a bit.
That was why I was thinking it was so much different than the new blade I put on my father's mower a few months ago when his original blade was substantially bent, causing the mower to vibrate and rattle.
That was why I was thinking it was so much different than the new blade I put on my father's mower a few months ago when his original blade was substantially bent, causing the mower to vibrate and rattle.