This looks like a separate topic to me. I see the standards thread as a place for posting links for relevant resources, but not the place to clog up the thread by discussing them in detail.
I have some responses to Matthew’s post but some of it will have to wait til next week. For now I’ll point out that train track ballasting and MILS are two separate things. In the thread that Dan linked to, the MILS link is the first one that Evan links to, you definitely wanna check that one out. The purpose of MILS – which seems to have gotten lost in the discussions around here – is for landscaping the display and connecting the sections accordingly. You can MILS without train track (I plan to do it for both castle and space) and you can have train track without MILS (plenty of LUGS do it).