Each time you merge, you get a random Tier and you pay a small fee (decay of Fuser).
You might end up with a worse Tier than you had before, or a better one. You can not force a good tier.
The chances are the same each time, no matter if you merge a 99% item with a 1% item or 2x 50% items.
To do what you think of (99+1) you will need LOTS of 1% (or one shot) items. So you buy (and/or shoot) or loot hundrets of items to
maybe get a good Tier....
Crafting / BP (L):
No, i talk about BluePrints, such as Welding Wire (L). Its not too uncommon for a crafter to have lots of them, i had at one point around 120 BP of Welding Wire. They had from 100 Clicks to 10 clicks each.
If you want to craft them you constanly need to put a new BP in the crafing machine. You can´t sell them well at auction even they do have a good MU because you could only sell those with atlast 100 Clicks.
The Suggestion says that you can merge (L) BP unlimited = You might end up with a Welding Wire BP (L) with 1200 Clicks (12 PED Value) which you could easly sell on auction or craft in one row.
PS:
I don´t understand:
Which problem has not been adressed?
See here