A couple of months ago, my members asked me to start posting stimp readings on a weekly basis, I take them on Friday and put Friday's result up for the weekend, they usually don't change a lot. So far it hasn't caused me any problems, but I always understate the average speed by about six inches, going with the slowest green.
It's plain stupid to overstate the speed, because one day some one is not going to believe you and demand to see it, and you're going to look a world-class ass, and your credibility will be gone forever and always. It would be like getting caught cheating at golf - no one will ever want to play with you again.
Also, contrary to past conventional knowledge, with the new growth regulators, greens do not necessarily slow down as the day goes on. My greens regularly stimp their fastest from 1-3 PM, anywhere from 2"-8" faster than right after the morning mow. I think it's because the surface has dried and there's less moisture to stick to the ball, and the growth regulators have all but stopped the blade elongation.