I got curious and decided to calculate the absolute limits for averaging items, so here's a guide to calculating this for an arbitrary count or grade of items (as well as a few examples at the end).

EDIT: I'm a fool and did it for arbitrary levels because I like math. We're bound by 99, so this just needs a table – there are only 9 cases, it's much easier to just check.



To use the table:

If you have 6 G84 items, you can bump an item of more than or equal to G(84-16) = G68 up to G84. If you have an item of G70 and you want to bump it up to 100, you need (100-70) = 30 => 17-32 range => 7 items of G100 to bump it up.

Old explanation post:



DOING THE ACTUAL AVERAGING

Okay, so you've done the math checked the table, and it can be done. Now how do you actually do it? Let's say you have one item of G70 that you want to bring up to G75. You need 5 items of G75 to do this. Detailed steps below, and I've put the item count between each step.



And there you go, you now have 6 items of G75. The number of steps you need grows very quickly depending on how big the grade difference is, and it can get a little hard to keep track of everything.

Another check you can do if you have enough items is jumping items up directly. You can do this to items with a grade difference of count/2, rounded down. If you have 8 items, you can immediately jump an item 4 levels higher; if you have 21 items, you can jump an item 10 levels higher. I use this in steps 10 and 11, as I have enough items to jump an item of G73 straight to G75.

I hope this helps people and that it's not too technical now that it's not too technical! Let me know if you spot any mistakes in my calculations, and especially in my example – the numbers started to blur together at the end.