Granite 4.1 Architecture Changes?

Hey all. Anyone know why IBM decided to return to a pure transformer model for Granite 4.1? They mention in their release post that it's easier to fine-tune than Granite 4, but surely the drawbacks outweigh this benefit, especially for a model that is often used for very well-defined basic tasks like document summarization, translation, et cetera, which don't particularly require fine-tuning? Perhaps it's a consideration for tool calling? Granite 4 used a