There really isn't a comparison between the two. Given the same bullet weight, it's simple, the bigger powder capacity and heavier loads of the .41 magnum are always going to be faster and more powerful. The same will be true of the .40. People believe what they need to believe to get themselves through life and changing their beliefs (note that I avoided fact or knowledge) is just not worth trying most of the time.
I read an article about the 9mm federal that declared that it approaches the power of the .357 magnum.
Sure, it does. Every time I go out west, I'm "approaching" that god awful huge line of mountains, and it takes five hours before I reach the mountain.
Things are relative and people love to take advantage of the "relatives". A ford pickup is a bit bigger than a pinto, if you are putting them both relative to a peterbilt.
The truck is a bit bigger, the peterbilt is a LOT bigger.