zebrad: clarify hedge layering motivation
@@ -143,6 +143,11 @@ where
// layer is relatively unimportant, because slow requests will
// probably be pre-emptively hedged.
//
+ // The Hedge goes outside the Retry, because the Retry layer
+ // abstracts away spurious failures from individual peers
+ // making a less-fallible network service, and the Hedge layer
+ // tries to reduce latency of that less-fallible service.
+ //
// XXX add ServiceBuilder::hedge() so this becomes
// ServiceBuilder::new().hedge(...).retry(...)...
let block_network = Hedge::new(
