Originally from cross-country running, a dog trail is a path that cuts away from the main course. It sometimes enables a runner to get away from a crowded pack and return later, further up the course. The dog trail is often longer, but being less crowded can sometimes cut the time to advance in the race. Nonetheless, it is a risky choice to take. In business meetings, a dog trail refers to going off the main topic of discussion focusing on barely related ideas one individual wants to promote. This can often prolong the discussion, even when the resultant conversation could ultimately be fruitful.
Bob has taken us on a dog trail Let's get back on topic and complete the meeting.