Direct Wire 4ft T8 were purchased and installed. Is there a rule of thumb or recommended process to burn-in the bulbs?
Is there a good test or process to weed out 'infant mortality?'
Most modern lamps do not need a burn in period. You can just install them. As far as "infant mortality" I know of no field test other than install them and if you get a bad one it will usually burn out in 30 days or less. After that they shouldn't go bad for quite a while.