Software licenses aren't enforced by magic but they are social contracts: even if nobody has the resources to go after you for doing it, it is pretty clearly against the permissive licenses' spirit to misrepresent yourself as the author
It's also pretty clear that the real author gave you permission to misrepresent yourself as the author, as long as you retain the copyright notice. If he didn't want you to do that, he shouldn't have given you permission.
Wow you sound like a nice person
The "if they wanted you to follow the spirit, the letter should have been different" argument grants membership in the society of people known throughout history as "the reasons we can't have nice things"
And everyone who follows this argument has become filthy rich.
Incorrect, there are plenty of people who ignore or fail to recognize the purpose of a rule as a completely free service, as any forums mod or OSS project maintainer can attest to
they dont though. nothing about MIT license is granting anyone the ability to misrepresent as the author. thats why its a license and not copyright transfer.
You have to keep the copyright notice and the license. Everything else can be changed as you see fit.