Actually on the previous engine there was such limitation, but it's now a problem of the past, however you are bound to the volume ramp up/ramp down requirement if you don't want to blow up your shakers. For instance at 44hz one full oscillation is 22ms, considering you need two or three oscillations (not including ramp up ramp down requirement) you won't be able to go much lower than 50-60ms,
However on current version off simhub both shift makes it react (gear to neutral, then neutral to gear) which makes maybe a longer feeling.
I'm currently working on the next major iteration of shakeit, where i take all the feedback, learning and errors from those last 6 months of "shakeit" life. Basically keep the good, throw away the rest
"We can rebuild it; we have the technology,"