#2 is writing ATTN: on the envelope.
The envelope will go to the person who it's addressed to, until my understanding of the postal system is severely mistaken. Yet, many people feel compelled to add a line such as this:
ATTN: Agenta McAgent
Agenta McAgent Literary Agency
999 East 28th Street
New York, NY 10001
The intention is obviously to try to bypass the "lackey" (me) and land right on the agent's desk, as if our mail is processed by a machine designed to such things, or as if I am as dumb as bricks. I have never once seen an ATTN line (or anything else meant to indicate who it's supposed to go to beyond the address) and said, "My G-d, this is clearly a query letter not meant for me, the person in charge of reading query letters, but for my boss, who is busy on the phone with an editor. I'd better interrupt her phone conversation to pass this on." We're on to you. I do the queries unless I'm out of town. No amount of sneaky tactics can change that.
Actually, there are some envelopes I pass on immediately to my boss when I sort the mail. These are known in agent-speak as "bills."