That's a good question and I'm pretty new too so I've asked the same. Leave room between your boat and others (plus extra) for whatever gear they might be running - planer boards can be out to the sides more than 100 feet and wire/copper rigs running behind the boat up to 1000. If the pack is trolling East/West, cutting straight through headed North or South (particularly with no warning) isn't going to make you any friends.
The best example I've seen was last season, off Hamlin Beach during the summer derby, a very busy time for both charters and recreational fisherman. There were five distinct lines of travel, all headed East/West and staggered about every 60 feet of water depth. The boat to my outside wanted to cut in, hailed us on the vhf ("Calling white Starcraft, tan bimini top.", aboard the Jolly II...), told me what he wanted to do and asked what we were running. No fuss, no muss. Very glad he did too since we had a client fighting a nice salmon on a dipsy, back about 400 feet.