Wow! That attachment is friggin HUGE!
If you have multiple viewports at different scales, LTSCALE 1(although I prefer .5) and PSLTSCALE 1 is the way to go. Ditto if you have lines with linetypes other than continuous in paperspace. Otherwise it gets down to preference on doing it that way or LTSCALE = vportscale and PSLTSCALE 0. My personal preference is the PSLTSCALE 1 way.