Marcus, I tend to agree with you. I've often wondered why they (Showa/Suzuki) opted for this on a bike like the RM-125. I think it helps on 4-strokes which can generate a lot of chassis pitch....not so sure it's effective on a bike like a 125 2-stroke.
Trials - this is the Lo-Speed shim stack. Honda's from '03 to today have them (although with a huge side bleed). If you're doing MX, just leave it alone. If you were doing woods (or you are very light in body mass) you could flip the stack over. HOWEVER, I'm not a Race Tech guy, so I don't know how it would affect the RT system of valving, nor do I know what RT recommends.