Kudos to my buddy Bruce Johnson at William Tao for coming up with the issue and making me try it out...
Traditionally, the architect defines a ceiling grid in a project. The problem is that it isn't always correct in terms of layout so that the lighting works, so the engineer wants to create the grids themselves.
Enter Revit MEP 2010 - From the Architect tab, choose Ceiling, and then choose the Sketch Ceiling option. A new tab will open up and allow the engineer to create the boundary for the grid. If drawing lines, make sure you're using the chain option to tie them all together (I used rectangular for the boundary for proof of concept). Be careful with some of the snaps, as it may leave you with a open boundary error - if this happens, turn off the snaps and use the listening dimensions to drawing the sketch with the correct dimensions. Once the boundary is drawn, go to Ceiling Properties and check the grid type you want. Choose Finish Sketch to complete the command.
You can lock to boundaries to wall faces if needed, but if any of these constraints don't work you can use the good old fashioned manual method...
And you CONSTRAIN THE LIGHTS TO YOUR GRID...which means when the grid moves laterally, the lights will move as well.
Try it out - let me know what you think!
later - dab