I have been running modafinil for five years and the honest summary is that the effect is smaller than the internet suggests and real.
The comparison group matters more than the compound when the outcome is something as fuzzy as focus.
Mechanism is not outcome, and a plausible pathway is the most expensive kind of evidence there is.
My rule now: if a claim cannot survive being written down with the numbers attached, it is marketing.
The measured outcome and the hoped-for outcome are rarely the same thing in these threads.
Happy to be corrected on any of the above.
Narrow conclusion.
What is the first thing you would read if you were starting from zero? How long have you been on modafinil?
Loose evidence is not nothing, but a washout either side is the only reason to trust your own take.
If it needs three other compounds to notice, you have not tested the first one.