rabidcow mentioned some of the issues with multimon, but..

real negative coords doesn't really have anything to do with multimonitors, they just avoid "wrapping" with negative values. the coordinate system used is more relevant, though with coordinates relative to the primary screen you need real negative in order to specify a position on a monitor to the left/above the primary screen. lsdynamic uses virtual screen coordinates tho, so coords are relative to top/left of the desktop (the bounding box around all monitors), ie. everywhere visible is at a positive coord and real negative is only required for coords off-screen.

so you're right, that script should let you move any module relative to the virtual screen even if the module itself uses primary screen coords. you don't really need the ifs though, unless you want to force wrapping to not occur (not necessary for multimon support in this case).

"real" multimon support would let you specify coords relative to a specific monitor, but that requires a lot more work like rabidcow's special ls-build, so support in this case only means the ability to specify a position on any monitor (not relative to the desired monitor, which is noticeable if the monitor is in a different place from what your theme assumes or you move the monitor.. better than nothing tho)