Curious- base coat vs acrylic urehane for base

If you use fast reducer/hardener in the hot weather, it may actually dry when spraying and result in a dry/flat looking finish or even the worst orange peel you can imagine
I use PPG I sprayed my cars with 85' temp reducer in 70' weather. Lets the paint flow nice. If you don't know what your doing you can flow a lot of runs. Fast reducer I agree as qouted and will not adhere properly and likely lead to peel as paint can't bite to primer if it dries to fast.