LOL, no he was referring to switching to GPT BEFORE A CLEAN INSTALL. And if you are doing a clean install the first time using GPT EFI, the drive has to be prepared manually or using windows disk part, which is not always successful.
I am not going to debate, as I have did hundreds of installs. You put in a new HDD or switch from BIOS to EFI and try just to install windows using EFI and good luck. You have to prepare the drive first manually or using windows disk part. It is not rocket science.