I'm thinking that is too vague. It takes precious little time to rack a slide while bringing a gun up from a holster, in fact, maybe no appreciable extra time at all.
Ah, but it does take extra time. Time that you may not have. It also assumes that you have both hands free for the task. Oh wait, you practice one handed too.
Okay wyocarp, how quickly can you draw and rack the slide on a semiauto when your weak had is busy fending off a person trying to stab you or hit you with a club? Have you practiced being able to do this?
How quickly can you draw and rack the slide when you are using your weak hand to drag a loved one out of the line of fire with it?
How quickly can you draw and rack the slide when you are using your weak hand to staunch the flow of blood on your own body?
How quickly can you draw and rack the slide and your dominant hand/arm has already been disabled in the fight?
People who talk about drawing and racking almost always talk about having both hands free for the task and in real life, we don't always have both hand available for such a task. Now, it isn't so much of a speed issue anymore as it is an issue of just being able to successful accomplish the task and if that gives you problems, it will take a LOT more time. You can learn to do a one-handed rack, but it takes time and increases the risk of inducing a malfunction if not done right, thereby necessitating more time to have to possibly clear the malfunction and then re-rack the slide.
A lot of folks don't practice one-handed racking and a lot of ranges won't allow it to be practiced because it is considered a dangerous way to handle a gun, and it is more dangerous to do than doing it in a traditional two handed rack method.
But hey, if you want to carry without a round in the chamber and feel safe doing so, you are just handicapping yourself, but you apparently don't feel your handicap is enough to give the bad guys an advantage. Good luck.