Simple really.
If you stopped reading reloading manuals around 1972, and ignore the advances in bullet technology in the last 10 years OR...if you are just a cheap SOB and only want to use bulk C&C bullets, then yes, shoot the 180's and don't look back.
However, if you HAVE kept up on bullet technology, you understand that everything you ever knew about bullets is now thrown out the window and irrelevant. Hard for a lot of people to grasp, because humans as a species fear change in any tiny way, especially hunters/gun nuts for some reason.
Modern, what I consider "super premium" bullets, are NOTHING like the bullets of old. Using the heaviest available bullets in a caliber to insure deep penetration was a problem with crappy soft bullets from over 100 years ago. Period. End of discussion. Its like comparing a modern direct injection multi-stage cam lift engine vs the Model T's engine. They don't compare except the fact that they are in fact inside a car, and make it go vroom.
With these new super premiums, penetration is damn near guaranteed to exceed anything else, pending the animal doesn't have a 6" steel plate around its heart. Sure the old bullets killed just fine, still do. BUT, humans while fearing change, also crave advancement (we are a funny lot). Metals are better, machining and tools are better, powders are better, primers are more consistent, bullets naturally are in the same line. You simply do NOT NEED anything over the "medium" end of bullet weights in any given caliber for todays modern bullets. This has been proven through hundreds of posts on various forums, articles, testing, and lab work from bullet makers.
Want to use cup and core soft points on an elk in 30-06? Sure, use 180's, heck 200's are better. Using a multi-part bullets such as the Partition or A-Frame? 180's is cheap insurance but you're probably fine going lighter and 165's will do the job just fine, this goes for bonded core bullets too.
Now, if you are using monometal or non-conventional style bullets? 165's and under, and you'll have NO issue, damn near from any angle. I wish someone would do some penetration tests here so we could see, but I know over on AR guys have used the 130gr TTSX in 308 mags to kill elk just FINE. Most guys would scoff and say a 130gr will bounce off even the tinniest of elk!!! How dare you insult the game by using such a small bullet?! But they forget, Barnes bullets will almost always give full penetration, regardless of MANY factors.
They shoot flatter, meaning less hold over or trying to do math instead of concentrating on the target. They recoil less, which means you can shoot larger cartridges comfortably, or just practice a whole lot more. Might get rid of that flinch too....no one will admit it, but I bet there are more then a few people reading this now that developed some bad habits by sticking to old lore with shooting. Most won't also admit the 30-06 with 180's is just too much for them. But, I know they exist, I see them at the range, flinching at a shot with 8-9lbs 06. If they were shooting 150's I bet they'd do better. I know the 130's in my 300wby are cream puffs on the receiving end of the recoil.
SAYING ALL THAT....if a 165gr partition makes it through eland, then there is absolutely NO reason to "need" anything more. African game are not bullet proof, I think that perception became of physiological differences then what US hunters are used to. Whitetail hunters are used to the high shoulder shot...well, don't always work with every animal lol
