...I think I used to be far more concerned with the ideal pressure when I was running narrower tyres, now I have nothing under 40mm I'm checking less often, maybe I've just become lazy!
For me, if it is a long ride, I am more likely to top up the tires. I rode my errand bike to the gym and back today, 3 miles (~5km). I can't remember the last time I added air to the tires on that bike, but it would not surprise me if they are down 20 psi. But for that distance, who cares.
My Joe Blow pump gauge is spot on compared to a couple of digital gauges I have.
I agree with you, the narrower tires, I am more careful to make sure I do not have them too low.