Third Hokage was stated to be the wisest hokage in history. He could likely deconstruct it's mechanics through his wisdom like he deconstructed Truth seekers mechanism within seconds.
Just because he can doesnt mean everyone can. Not to mention Kakashi thought it was impossible for someone to master all 5 elements without having a extra power like Kakuzu's, to gain the ability to wield all 5 perfectly. So I'd say the Third wasn't normal just like Hashirama who inherited the Juubī Mokuton directly. Considering his parents did not have it. Both are God of Shinobi so maybe common sense doesnt work with them. The highest amount of elemental transformation a single individual can use without mastery over said element is 3. With mastery its two, considering Sasuke has two elements mastered and hes an all time genius.
So yeah, you cant master all 5 but you can master yin and yang along with any two of the basic elements.