going into and out of the lucky 38 will trigger a contact by the NCR, even if house wasn't talked to.
interacting with benny and leaving the tops will trigger a contact by the legion. if dealing with benny before entering the lucky 38, the NRC will also contact the courier.
if the chip is taken to the bunker under the weather monitoring station, without talking to house at the lucky 38, house will force a conversation before the courier can go further into the bunker.
if the courier is given a quest to destroy the brotherhood and haven't been there before getting that quest, the brotherhood will emerge before the courier can give the password.
if verronica is to join the followers, no attack by the brotherhood will take place at the follower's outpost until veronica goes there.
if the courier's rep is high enough with the brotherhood, she will still be a sidekick if the bunker is destroyed.
do i got it right?