For the most part bullets that shed weight have been dropping game for about as long as the powder has been around to drive them.
Like Ants mentioned, you can drive any bullet fast enough, and into something solid enough, that even your precious Barnes will shed the petals and drop weight.
Personally I gave the Barnes a good going over years ago, and moved on finding they offered me nothing any more spectacular than what the standard C&C bullets costing half their price offered.
While I have not shot a bull elk, I have shot a cow, and did so with standard C&C 180gr factory load, and total distance from bullet impacting shoulder, to shoulder impacting ground, was about 30'. Might have just been a fluke but the insides looked like strawberry jello to me.
I have shot hundreds of deer and hogs with all types of bullets, and not found that the higher dollar bullets work any better overall. Put the shot where it is supposed to be, and nothing but jello from either of them. Now I will freely admit that there is a place for them and that is usually with a high octane round pushing them out at over 3200fps from the get go. I used the 115gr Partition almost exclusively in my 25-06 as it worked as good at 10yds as it did at 400, whether it shed the frontal portion or not. It didn't blow a huge bloody mess into the side of a deer that I had to trim and toss. I also admit that the 115gr Barnes X worked equally as well, but at the time they also cost more and were harder to find.
In another example, I used the .308-130gr TSX for a reduced load for my grandson. It served the suited purpose perfectly. It had enough weight to penetrate, and being built the way it is, it held together just fine.
Now if one shoots 50 rounds a year some of the high dollar fancy bullets might be worth it to them for a bit of added insurance, but spending the same money on twice the amount of cheaper bullets, and using half of them for practice, will go much further in the field. I'm not knocking the premium bullets as they do have and serve a purpose, but they aren't the end all king of anything that shoots. As for making up for a bad shot, I admit they penetrate, but if you have to rely on that much penetration for medium or big game, you might need to reconsider the shot to begin with, unless your hunting stuff that might hunt you back.