I have never kept my chicks any higher than 90F. I don't measure the heat any longer - because I use EcoGlows, but this is what I did when I used heat lamps. However, at 3 weeks they are completely off heat here. If I go by what you say, they should be at 80F at week 3. They are at 70F, and around 50 at night.
I've raised roughly 200 chicks this year. I've hatched 1500.
I am not sure where everyone gets this 95F temp. I have always been told 90 or whatever they seem comfortable at. There is no magic number. Monitor them. If they seem cold, add more heat. If they seem hot, take it away.
My chickens are Canadian. 85-90F seems where they are the most comfortable at a day old. 80-85F for week olds. 70-80 for two week olds, and by 3 weeks they don't have anything in the summer.
Chicks aren't as delicate as they are made out.
This pic is taken February 22nd 2013. These chicks were roughly 6 weeks old. I hardened them off in the basement by leaving the window open. They were out without any heat in freezing temps. All are adults now. They do just fine. The EcoGlows were removed when they were 4 weeks.
Agree - other than I don't have an EcoGlow