The new Expanded Inventory View design

[Vaer]

interesting. So there are "chunks" of inventory and the server reacted poorly to larger chunks, so they pared it to more chunks and swapped some over to a whole new way of saving it in the dresser and the chocobo bag.
looks like the UI is a problem in mac and 32 bit clients too.
Nice to have some insight.

They wanted to add another 2 bags after the 4 bags we already have, but when they were making ARR to save time they appended other item data (temporary trade data, mog mail items) after the 4th bag.

To add the 2 more bags they wanted they would have to deal with all the other item data that is being stored after the 4th bag (according to this they would have to modify that block and get the original programmers on board).

Instead of wasting more time and resources doing that, they just increased the size of the 4 bags we already have by 10 slots. They then used some code to sort and parse the display of the 40 extra slots since the UI was still in groups of 25 instead of the new 35 in 4.0. (I guess this is why it looked like they just glued 40 slots to the end of the inventory)

In 4.1, they redid the UI to match the new 35 items per group and split it into 2 tabs to accommodate older OS and want to add 4 groups to one page for the OS that can handle it.