Right Piotr, I have pitched dry yeast in aerated wort and unaerated wort and had a slightly longer lag time with the unaerated to the tune of about 8 more hours. Results were based on my observations of when the airlock started ticking away. My fermenters are airtight.
My last batch of APA I did not aerate (on purpose) and I noted that when I woke up in the morning that the airlock still had no movement - no CO2. I thought it was odd since normally they are going strong within 12 hours of pitching, so I went off to work, and when I came home it was already ticking away.
Nice research by the way. I thoroughly enjoy topics like this!