"Compound requests are by far the fastest. This indicates that my original guess was wrong. Even when caching comes into play, it still can’t beat just re-sendi

"Compound requests are by far the fastest. This indicates that my original guess was wrong. Even when caching comes into play, it still can’t beat just re-sending the entire collection again in a single compounded response." TCP is heavily optimized for shoving a single stream of bits across the wire. The other options have more overhead from multiple requests.