DY >> You are too quick to assume you don’t have one.
this is, of course, a valid concern for all of us. I personally was involved in a couple of competitive intellectual pursuits over years, so I know what I don’t know reasonably well. As an illustration of me knowing my limitations, I realize that I can’t convince common sechel that I am not doing my halachik root canals – nor do I need to.
More generally, routine memorization of material will not give you an ability to know what you don’t know. One would hope that Talmud learning should give you some feeling what you can and what you can’t figure out. Maybe ask your own Questions and answers, and then go thru commentaries to see if you made a mistake…
Another story (with the same Rav): he gave a parsha dvar Torah on shabbat first to non-observant students, and then to observant. When he entered the second room, he would stand for a minute without saying a word. I knew that he typically discussed same issue that bothered him in multiple talks during the week. So, I asked him why he was pausing. Was it a trick to force listeners to quiet down? He admitted that the topic was the same, but he explained that he needs to re-work how he talks about it: students from Jewish schools were trained to listen, but he wanted them to first understand the problem and (sic!) start asking questions. So, he had to push them further.