However to know any single halacha properly one needs to know the Talmud from where that halacha comes from.

As for Halacha in fact the only valid source is the Talmud. But because not everyone has the time it is perfectly fine to go by the Rambam or the Tur Beit Yoseph. The only Achron in Halacha I have much respect for is the Aruch HaShulchan. There are people that go by the Gra in every detail like Rav Zilverman in the Old City. These are all very good approaches. However to know any single halacha properly one needs to know the Talmud from where that halacha comes from.

As for the other issues like problems with all religious teachers  being creeps that I brought up in my essay. I would not say what I say if I did not know it to be true.  And like I mentioned before there is such a thing as group behavior.  There are plenty of examples of this in the Gemara. See the end of kidushin "Where it says stay away from that group that are from such and such a city because they are all liars."  In any case my essay was really meant to address a public problem which is very real and everyone knows it except the people that want everyone else to be blind. 

And there are the obvious exceptions of people that are sitting and learning Torah all day who can be trusted and in Israel there is in fact is pretty good rigorous system in place. But these are side issues and tend to detract attention away from the widespread catastrophe that surrounds us.

It is for good reason I have mentioned the importance of  a legitimate Lithuanian yeshiva. If you do not have one there, then at least  get the book of Rav Shach so you can be yourself a walking Litvak Yeshiva, keeping the whole Written and Oral Law. Get to you also the books of Rav Chaim Soloveitchik and the other great sages of Lita.
[For example, the Even HaAzelof Rav Isar Meltzer, the rav of Rav Shach.] My learning partner, Dadvid Bronson, had a mind that could go deeply into Tosphot , but I know of no achron with that capability. So I confine myself to recommending the great sages of Lithuania that had a more global approach.
[What people call halacha nowadays is a joke. They take the majority of the frauds and liars that are as crooked as snakes and go by the majority opinion. That is what they call Halacha.]