In practice it works because "MSL_Labtime" flows across the entire vessel, but time calculation has to be fudged because the experiment steps only look at the current lab.

It might be better to try either of the following:

1. Have the MEP generate MSL_Labtime as well, and turn off flow
2. Find a lab which can generate the required resource in the vessel, and attach it to the step
3. Require the experiment to be "prepared" and "finished" inside the MSL-1000 or MPL-600 - this would require moving the experiment between steps as well as a "preparation" equipment rack which can be installed.

I like the last point the most, but it would require generic lab slots for equipment. So this might be for NEOS V2 unless I can figure out how to upgrade save files.