Even the best tank commanders found spotting AT guns difficult. The infantry compontent of armoured divisions is minimal, maybe 1/3 of the total force of the division. There are constant examples when they were not effectively supporting eachother (the Infantry was late, or the tanks were late), and in most of the attacks, the infantry fared better alone than the tanks. Just saying that they could spot AT guns easily, does not mean that they did! Most cases, AT guns were spotted just after they fired.
Tanks may be the only unit able to engage other tanks after a breakthrough, but listen to what I said, am saying, tanks are not the optimal unit for fighting other tanks. Casualties on both sides will be very high in a tank v tank battle, even though there would be no other option. In most cases, tank penetration attacks were stopped because of a stubborn infantry force rather than an effective armoured counter-attack. The Germans wore themselves down on the entrenched Russian Infantry at Kursk (which was a fortress), and both sides suffered equally horrendous losses. If you can easily replace losses, then tanks are a good weapon against tanks.
Tank losses are always high. The Germans lost hundreds of tanks in the Polish campaign, and hundreds more in France. Since they controlled the battlefield, they were able to recover and rehaul many of these lost vehicles, but they were effectively knocked out. These were relatively easy campaigns. The ratio of infantry casualties to total infantry was significantly less than the ratio of tank casualties to the total tanks deployed.
Quoting a tank commander to show the importance of armour is like quoting George W Bush to show the success of the US Federal government in the past few years. Pretty biased in my opinion.