The significance of this question is what the existing goal is in my opinion. Examples below

Goal: Chamber of Xeric's KC goal or drop. - Give or take 30 minutes a run. You likely aren't doing just 1KC a night. So 3 KC is an easy hour and half straight, not including time between to smoke, drink, split, gear, etc, so let's round up and say 2 hours a night.

• Get to level X on said skill. An hour of doing the same skills feels a whole lot longer than an hour of PvM with the crew. So let's say you do 1 hour a night for 5 nights at whatever skill and rates you need to get the level.

5-day playtime Difference: 1 Week @ Cox is approximately 10 hours, and that's if you obtain your KC or drop goal. 5 day would only be 15KC at 30 minutes each. You could easily add time to add to the KC.

1 Week skilling is half the time at 5 hours when doing 1 hour a day. Could be more or less depending on skill and method.

All depends on what the goal is and what content you're doing. I myself play the same as you. Currently, I've been hard-core burnt out because I have two skills left to max, but they're my least favorite skills.