Just be sure to stop a few days before hatch, and keep track of temp/humidity to make sure it bounces back quickly to where it should be. My best broody hens got off their nest daily for a half hour or so up until the eggs started wiggling - no problems then and 100% hatch rate, so no reason incubator eggs can't handle daily inspection. However, lockdown is worth respecting. Other than temp/humidity issues being more critical then, you can definitely distress a chick if you candle it after the internal pip...did that once to one poor egg not realizing how far along it was (it was a couple days ahead of schedule for that) and the chick started screaming in the egg from the bright light flash. That chick hatched just fine, but not something I will be repeating on any other eggs that are getting close to lockdown...