SMF import without affecting rhythms at all

Before I dig into Synfire, I want to make sure about this so that I don't waste time. The rhythms in the MIDI files I produce are polyrhythmic or irrational rhythms--whatever nomenclature you prefer to characterize things like quintuplets, septuplets, 7-in-the-space-of-3, etc. I want Synfire to preserve these rhythms exactly. I understand that Synfire applies useful compositional intelligence for pitches and pitch sequences, which you can override with the static pitches import. That's all fine. I want to make sure about rhythms because I don't see a "static rhythms" feature. It looks like Synfire's figures are for getting creative with pitches and that rhythm remains identical to the original. Is that correct?