While I agree with you, this is where training and experience come in.
In the Words of Chieftan, being shot at may constitute a significant emotional event.
While your training may allow you to operate the vehicle as normal in combat conditions, you are still not thinking under calm or perfect conditions. You will have adrenaline pumping through you ofr one, and thus your mind-set would be utterly different from if you were calm and collected. This can only get more apparent once shells start hitting the armour, crew start dying or things in general start going horribly wrong.
On the flip-side, aiming for weak spots was often irrelevant. Just as combat would effect the minds of the shooters, it would also effect the minds of those being shot at. A German panther crew does not know what they are being shot at when taking fire, and there plenty of accounts of crews on both sides bailing out of their tanks after being hit by rounds that didn't actually penetrate the armour, or inflicted mild damage. (often being tracked was enough reason to abandon the tank) Similarly, I believe the Allies achieved some remarkable success by simply flinging HE rounds at some of the heavier German vehicles, which either cracked the increasingly brittle plates or killed the crew via concussion, or made the crew panic and either abandon the vehicle, or attempt to drive away and get stuck, which inevitably meant abandoning the vehicle. Being shot at in general isn't really fun, and I don't blame the tankies for sticking around, even if it was statistically safer inside the tank than out of it. (a large number of tankers were killed while outside the tank, while inside they were actually far safer than most considering they were in frontline combat)
Post WW2 studies swiftly found the most important aspect of tank fighting was the simple matter of which tank shot/spotted/engaged first, and that if they did, they had something upwards of a 90% chance of winning that engagement, regardless of armour, gun, crew and such. However, having a good crew, being on the defensive or being well sited or supported are all factors which would contributed to you getting the first shot anyway, which is why the Germans often managed to get first shot capability, at least on the defensive. It was found that on the offensive, they encountered similar casualty rates to Allied armour, and more or less the same difficulties in general.