Re: instinckt or maths?
In a hunting situation, you don't always have time to fumble around with gadgets. So, your shooting solution needs to be almost second nature.
If it's pure guess work and you call that instinct, then hitting the target may be blind luck or slop which by some standards might be considered unethical.
However if it's supported by practice and experience and if it's repeatable, and if you call that instinct, then that would be better than someone who has to rely entirely on a ballistics program that may or may not have been tested/correlated with the shooters rifle/ammo.
I would suggest using ballistics programs to practice and develop the instinct for reading conditions and for making accurate shots.