[Kocur]

Now, did anyone who said that these planes were prototypes or haven't seen combat or were not production ready bother to read the top of the post.

"This is a list of planes that could have realistically seen production and done quite well in combat in a war that was harder on the Americans."

What attracts my attention is excess of optimism in that word...

Now, the XP-67 could have been put into production right away according to McDonnell. I wonder why. Oh, that's right, because they weren't making any planes. It would have been a realitively easy change too and it was all talked about. Swap out the engines for those mentioned above and replace the cannons with machine guns and start rolling them off the line. Try reading more then just one source next time, like a book.

If I were to return the favour, I would suggest to try to read about how much time it takes to test prototypes before "production configuration" is reached and then how much time it takes then to prepare production lines. Then there is a lot of time between planes leaving plants and first units being combat-ready. Like F8F: ordered in November 1943, prototype flying in August 1944 and first unit combat-ready in May-June 1945, and yet not making it to war. And that was a plane with no novelties, like new engines, all 100% well known technology, no change of propultion during development.
Could there have been mixed-power P-67? Sure it could, as it was well in envelope of technological capabilities. Could it have been realistically combat ready during WW2? No, not really.

Of course it takes no effort to change assumptions in one's alternative history. Like...
Could US WW2 fighters have been armed with modern Gatling guns? Sure they could! All it would take would be merely starting the program somewhere in 1920s instead of 1946, to get the same results as in reality after 18 years. Or twice shorter, had the desingers worked twice as hard. Or four times shorter, had they worked four times as hard...