Yes... that's their plan... Actually, it's even sneakier than that... The tierer gets residue back... which enters the crafting system... and makes all those globals appear, making it look like magical money is falling from the sky when it's really falling out of our wallets.
Residue added when crafting is *not* triggering a global.
As for items permanently lost I think that apples to SGA items - that a lost SGA item will never be looted again (with exception of a few specified armor parts that didn't drop during end of SGA).
As for the actual drop of ML-35's; the trend has been moving items to the biggest mobs ingame (Gauss HMV from beacocn mission to Mulmun Elite, Foreipper Atrax Young -> Atrax Stalker -> Atrox Stalker, Mod merc Goki -> Spider Stalker), so maybe MA will save them for something like the Mulcibers at an event spawn rather than dropping them from a regular Atrax.
The thing that makes tiering-up hard, especially if you're a mid level player with a limited amount of PEDs, is to get the second item need - if it's availible at all.
On the other hand, tier-in up becomes relatively hard quickly at higher levels. If I understand it right it starts to be relatively risky at level 3, and 4 is for the true enthusiasts.
When it comes to "tiering up" (L) weapons I guess we all know by now the tier values, what they mean; average values around 100 means it's pretty hard to get it up to "uber levels"; you need to be real lycky to find an item with good values to have a chance of bringing up an (L) item to higher values.
It took half the TT of my (L) umbra whip to get it to tier 1.0...
(It sucks of course since they are practially impossible to get a new one of the day it breaks.)