Three ways to make an LLM read its weights less often on a Mac — and why each one backfires

Single-stream decoding on Apple Silicon is bottlenecked by reading the model's weights out of memory, not by the math. Three techniques attack that directly — speculative decoding, diffusion generation, and self-speculative layer-skipping. I measured all three on a 16 GB M3. Each is right in theory and backfires in its own way: the bottleneck just moves one step further from the arithmetic.