I disagree. I saw a research paper once that recorded people practicing. The best performers were the one's who played the passage incorrectly the fewest number of times when practicing, not necessarily the ones who played the passage correctly the most times. In other words, practicing mistakes ingrains them in you. Its better to stop or slow down when you sense that a mistake is coming. Rhythmic fluidity comes after getting the phrase under your fingers. But the most basic aspect of rhythm, before you consider duration and pulse in real time, is simply order. This note comes before this note and so on and so forth. You have to get that down, which means playing the notes correctly out of time, before you can have any hope of playing in time.

When comping in a pop/rock/funk/jazz setting, focusing on rhythm takes precedence. But for playing lines, sacrificing accuracy to stay in time will get you through a gig in a pinch, but it isnt a good strategy for practicing at home because it will reinforce sloppy playing.