Chatbots normally write one word at a time and can cache earlier work. instead draft a whole passage and refine every word at once over repeated passes, so nothing can be cached and each pass redoes the full attention calculation, which is slow on long text.
Keeping only a chosen fraction of word-to-word links, a sparse mask, is one fix. This work refreshes that mask at a few checkpoints and reuses it in between, instead of fixing it once, and gives each attention head, an independent sub-channel, its own share of links.
The payoff: a 2.78x speedup at long context with most links dropped, scoring better than earlier sparse methods.
