Good questions & good points! As one can tell broadhead choice can really come into play here!
First I want to say that by trying to build an arrow wt. that will bust through anything is really not the way to approach this, sure we need penetration but we also need a reasonably flatter shooting arrow, you need the best of both worlds, 9-10grn per lb offers this. This wt. may be adjusted for large dangerous African game as should ones draw wt.on such hunts.
As George mentions "TUNED" equipment is of great importance, penetration & tuned equipment go hand in hand.
Pass-throughs are great but not necessary! I personally want a larger wound channel & don't care if arrow comes out other side or not. I will still & do get plenty of blood loss to track that animal.
I've had exactly the same experience with a 2-blade as EIGHTWGT has. His son got tons of penetration actually way more than enough, he went 3/4 the way through a deer but the shot was high. The cavity no doubt was filling with blood with little coming out the entrance hole. That's some tough blood trailing for sure.
I've shot elk in similar spots with zero blood for tracking with 2-blades. I've shot elk in those same areas with 3-blades, bigger wound channel more blood! Doesn't matter if the shot is a bit high they still bleed! I will state again, 2-blades will kill that's not the issue, the issue is blood on the ground on great hits & no so great hits.
For hunters to feel they must bust through leg bones to have a great setup is just not reasonable. This can lead to wounded critters. I avoid such shots & angles if at all possible. You could glance off left, right, up or down even though you're getting penetration, your odds are not good that on such shots you will dead center the bone hit & continue on with perfectly straight in performance! There are plenty of places to hit deer & elk without connecting with solid bone! For the record a 10grn per lb arrow with an Aboyer head for example will blow through the lower portion of an elks shoulder/scapula plate, no question in my mind!
You are not as likely to do this with a 3-bladed head, odds are very low! To penetrate scapula type hits you'd better also hope your critter is perfectly broadside, it's tough to penetrate tough bone on angled or glancing shots, they will have a tendency to skip or skid off. Point being, stay away from that area, you're too high anyway!
Too, 500grn arrows shot out of proper # bows don't bounce off animals! We've shot plenty of animals to back that up. Do a test of your own to build your confidence if need be! It's tough to base ones end all decision on one animal hit, the more the better & proper data can be accessed for the best results!
ElkNut1
It's like saying you hunt the wind but now you wear scent-lok & now I can forget the wind, not true & you will be busted by an elks nose!