@custommods Okay, I thought you were subtly claiming that you discovered this method lol...
Your belief on this being the best way to study tactics is probably accurate. Here is what the great M.V. Blokh thought about tactical study:
1. Solve tactical problems based on tactical themes (as you discussed in the video)
2. After going through a round of each specific tactical theme, solve puzzles that are randomized, which include all of the themes. He called this 'Conjunction of Tactical Methods'
3. Repeat the procedure all over again...
Although I enjoy Lichess' puzzles, it is comprised of the aforementioned Conjunction of Tactical Methods (all themes). I hope eventually this site implements theme based training.