There were many things that Lex did which were extremely confusing, and mentally strenuous. However, living simultaneously in two different flows of time was actually one of the insanely complicated things that he had gotten used to.
It didn't matter at all that in one second of Jack's life, wherein he may not have even finished pronouncing a single word, Lex lived for days or weeks. He had to maintain perfect reaction speed in both flows of time, making sure that he didn't speak too quickly as Jack or too slowly as Lex. It was the same for his every action and interaction.
Despite how unfathomable it sounded, that was something Lex had mastered pretty easily. He even managed to keep updated on the happenings of the Midnight Inn, which was operating in a third flow of time.
The thing that was actually bothering him was studying the aura remnants on his clone. In fact, Lex had dismissed his clone long ago. He simply captured the remnant aura, and continued to study it over time.
