Re watering - I live in the driest state of the driest continent of the world and we are well used to droughts, water conservation and the like.
I used to work for govt and we would constantly get complaints about watering occuring in the middle of the day, as tax payers think its wasteful.
It makes all the difference HOW you water. Govt watering is done at root level, and gives a thorough slow soaking. No burnt leaves (if the water doesn't touch the leaves) and the root system develops at a much deeper level if you water long and slow...which in turn makes the plant stronger, and more able to survive a drought in the future. It makes exactly zero difference what time of day it is.
If your environment is hot and dry, you don't have to worry about mildew.
The worst think you can do is stand there and spray with a hose, which is why we mostly have watering systems to deliver the water straight to the soil.
There is a heck of a lot of artificial turf and native plantings around because green grass just doesn't suit our climate.
Hope this helps the watering debate.