feedback: add note one time spent reading vs writing code

Author: conectado

content/concurrency-patterns.md

@@ -779,7 +779,7 @@ frame #1: channel-per-writer`tokio::runtime::task::core::Core::poll at core.rs:3
 
 This means it's reasonable to expect the value of the variable to come from some local function call, as there's nothing up stack we can look at in our own code. Let's trace back where `Message::Send(...)` comes from, then: first we can see there's a match with `msg`, so we need to find `msg`, which is defined a few lines above from `let Some(msg) = rx.next().await`. From just the line above`rx` is a combination of `write_error_rx` and `reader_rx`, `write_reader_rx` is a channel we created locally, so we can trace down its corresponding `Sender`, but `reader_rx` comes from the caller of `central_dispatcher` which we can't find in the backtrace!
 
-This is potentially a problem with any callback, but it's worse with channels. Even if you manage to track down where the channel is created, it doesn't tell you which the source of the received values is; for that you need to find the corresponding `Sender`. But as the `Sender` is cloneable, you could find it in multiple places. And more than one of those places could potentially send the same variant, making it impossible to correlate the function that sent the values with the value received in a normal debugger. This can make programs very difficult both to understand and to debug.
+This is potentially a problem with any callback, but it's worse with channels. Even if you manage to track down where the channel is created, it doesn't tell you which the source of the received values is; for that you need to find the corresponding `Sender`. But as the `Sender` is cloneable, you could find it in multiple places. And more than one of those places could potentially send the same variant, making it impossible to correlate the function that sent the values with the value received in a normal debugger. This can make programs very difficult both to understand and to debug; considering that for most of us we spend more time reading than writing code, this is a high price to pay.
 
 Contrast this with the `Mutex` version of `handle_connection`: