This debate about Reid is funny. Funny in that it is the same argument people have been having about Belichick for years. Is it the coach? The QB? The Defense?
If you look back at a list of coaches who have won super bowls and compare that to the QBs that have won SBs, to me it looks like it is usually a top coach who wins. A few oddballs along the way but mostly it is all the top names. If you look back at the QBs, still a lot of top names, especially of those who have multiple, but there are a lot more Trent Dilfers and and Brad Johnsons and Nick Foles that have won.
Of course Reid is a better coach when Mahommes is the QB. But KC has a good OL, a good defense, they are a well coached team. Just like the Patriots all those years.