It might be that you focus accurately but don't think carefully about where to focus and when observing your results you feel a sense of focus deficit, when the problem was just in focus planning so to speak.
Generally speaking, focusing has its importance but shouldn't detract too much from other technical aspects of photography.
Is the real problem one of incorrect focus, or improper choice of focus point, or something else that seems to affect focus?
There are few categories of photography that really challenge any normal focus system.
“Wise men talk because they have something to say; fools, because they have to say something.” - Plato
Well the situation that tested me - and at which I failed - this weekend was a fashion runway show (Chattanooga Fashion Week) in which my daughter's designs were included. The lighting was very low, I used a flash to help, but focusing was a challenge. I'm sure my eyesight is not as good in low light. The lens was a Nikkor 35 - 135mm f3.5-4.5 which contributed to the challenge because of the relatively small maximum aperture. I think it is right that some "focus planning" is important - I could have pre-focused on more spots to have a better idea where on the lens barrel I should be at various stops along the runway; I should have used more power in the flash for a smaller aperture and more depth of field, etc. It seems the digital guys just set their cameras on ISO 6400, everything else on auto, and have auto-focus. They get great results but I don't think I would enjoy photography that way. I prefer to make mistakes and learn from them, rather than make no mistakes because I'm not really doing anything.