Or, "the packet is sent from the client to the server, and it ...." I see this a lot in technical writing where the writer is explaining a flow of code or data, and is very well aware of the antecedent of it - but the reader now has to guess, read ahead, perhaps discover they were wrong, revert their mental model, and make a different guess. JRY - Just repeat yourself. Be unambiguous. Use whatever word would have been the antecedent of the pronoun, and let clarity shine thru.

another pet peeve I have is double or even triple negatives used casually. Newspapers like the NYTimes or Wall street journal are very guilty of this. For example: "The congressman voted down a bill banning opposition to Foo".

Of course, this statement is factual, but it's extremely difficult to tell whether the congressman is in favor of Foo or not. Simply contracting the sentence to "The congressman (doesn't?) like Foo" loses info.

I think the proper solution here is for the newspaper to have the original confusing sentence, but also add a second sentence with the contraction as a hint. For example:

"The congressman voted down a bill banning opposition to Foo. He did this because he is in favor of Foo."

This kind of ambiguity is rampant in technical writing. Example: "There are situations where developers do X instead of Y which is the wrong thing to do." Wait, is X wrong or Y?! You go ahead and assume X is wrong and then figure out later they meant Y is wrong or vice versa. Argh!