Trigger time?? Maybe... maybe 20% to 25%.. I'm old, retired, and in no hurry. I sharpen ( touch up), after every tank. Does the chain actually need to be sharpened? Well, probably not, but it's a good excuse to take 10 minutes of not running the saw, and especially if it's hot out, to grab a cold bottle of water, and relax a bit.
If it looks like it's going to be an all day job, outside of fuelling and sharpening, there's still a 15 minute break in the morning, another in the afternoon, and a half hour for lunch. So, out of an 8 hour day.. take off a hour for breaks and lunch, take off another hour for set up and pack out / clean up.. It's really only a 6 hour day. 20% of that only 73 minutes of actual trigger time.
If I'm the only one running a saw, I may put in a higher percentage of trigger time, as someone else is dragging brush, loading for the splitter, etc. But, if I'm by myself, ( something that I avoid, unless it's a small dead simple job), since I've got to do it all, yeah, probably around 20% trigger time. If that.
Getting older, I will wear my anti vibe gloves if i'm doing more than a couple of cuts. Cut up more than 1 small tree without them, and I've got the "tinglees" for hours. Cut for the day, with AV gloves, and there's no tingles... ever.