After shooting a walking bull and loosing him a few years back in Colorado I will NEVER shoot at a walking elk again unless he is under 10 yards.
~25 yards, 100% broadside, walking and I held slightly forward between green and red and hit 1" low of orange when that bull took 1 step.
Then had help from unforeseen other "hunters" to run the bull to parts unknown. I still have nightmares about the loss of that elk.
You hold red and that bull takes 1 step there is a good chance you will never recover that animal if he is hit with an arrow. Just saying.
If I could do it all over again. One simple "Mew" Zap....he would have been mine.
Being a lifelong bowhunter I know this, and knew this at the time. Not sure why I chose to shoot at him walking but its a decision I made that I regret to this day.