Elk are the anomaly. Most folks agree mechanicals are decent for deer and smaller, aside from those who have had bad experiences. Conversly getting folks on board that a heavier arrow and COC 3to1 are needed for buffalo or trad equipment is a pretty easy argument as well.
Elk with modern equipment is a conundrum. You don't see alot of videos of 90 yard shots at Buffalo, or frontal, or quarter 2 hits into guts, or single lung. Elk are hunted by calling, spot and stalk, ground blinds, tree stands and every other tactic you can think of. Many hunters do not have the luxury of multiple encounters in a season, and pushing the envelope on shot selection from both angle and distance standpoint is the trend.
I will use an example that happened to me this past season. For the record, my setup is a 500 grain arrow at 285 fps, 15 percent FOC and I was using a mechanical broadhead. I had a gorgeous rosie bull at sub 40 yards. The bull was quartered to pretty hard. The angle he presented was such that a shot very tight in the vital V was the only option for success, inches to the right it hits the knuckle, inches to the left and it hits one lung and guts. He was not quartered enough to go for a frontal shot. As I assessed all of this in the seconds he gave me at full draw, I opted to refrain from shooting deeming the situation as a whole a low odds of success. I hoped the bull, would slowly turn away opening up as he went, but he swapped towards me and cut out of there. I ended up having to wait 34 hours to get on him again.
I beleive this exact situation is why the broadhead debate is hotly contested. Let's say I shoot. Odds of a few inch miss for me at 40 yards is dam low, but certainly not outside the realm of possibility, i am rushed, in the heat of battle, and pouring rain and only seconds to figure out this
shoot not shoot scenario. IF I lace the bull perfectly, most likely either head is a winner. Yes, the mechanical is at a disadvantage as it is likely to contact the tight ribs and muscles of the bulls front end, but odds are good pentration will be enough to be effective. The single bevel has clear penetration advantage, but at 40 yards pinpoint accuracy forgiveness could be a factor. We are talking about a fist sized right or left window without either major bone contact or missing heart or both lungs.
Let's play it out as I miss a few inches.... to the right. Single bevel becomes the hero, potentially breaking through the shoulder bone, maybe even the knuckle severing arteries and probably killing the bull in seconds. The mechanical is a horror story, and probably falls out after 4 inches of penetration. To the left..... almost a complete opposite. Both heads cut one lung. The mechanical cuts 2x as much lung tissue, is at least 2x more likely to cut the liver and/or diaphragm and more likely to leave good blood in the downpour. The single bevel, will likely pass thru, leaving far less damage in it's wake. Possibly even more of a problem its less likely to leave major blood on the ground. We could get lucky with either head and have it be stuck inside cutting as the bull moves, both cases are good but again the edge goes to mechanical due to its higher likelihood of staying in the cavity and the increased trauma potential.
I really think it's hard to argue with a quality 3 blade fixed for mixing the two worlds, but its certainly not the best of both. In the end I opted to pass and I still don't regret that decision.