I think that “teach” has a different meaning here. There is “understanding something well enough to elaborate it in its entirety” (the technical capacity to tea

I think that “teach” has a different meaning here. There is “understanding something well enough to elaborate it in its entirety” (the technical capacity to teach it) and then there is the former + “and have the skill/talent of being able to explain it to a wide variety of other people from different backgrounds.”