How tight to set solid lifters

There are varibles that can affect lash, hot vs cold. Cast heads vs aluminum heads, cast block vs alum block, aluminum vs steel ball type vs steel roller rockers, stainless valves vs titanium valves, intake valve vs exhaust valve. Etc.
For me, I'm not sure it's worth figuring out exactly how much all the potential combinations affect lash hot vs cold. Just knowing they might is enough.
The lash on your cam card is a recomendation. If you call your cam manufacturer they will give you a safe range for lash settings based on the cams profile. For example you may find that extra little bit of vacuum you need by setting the lash at the loose end of the range. When we sweep the lash at the dyno to find what makes the motor happy we do it with the motor hot. Since the motor is already hot it wouldn't make sense to wait for the motor to cool off just so we can set the lash cold and then warm the motor back up for the next pull.
If the customer wants to set lash cold that's not a problem. He can check the lash with the motor cold when he gets home and set the lash to that measurement for future cold lash checks. And if he wants to or has to set the lash hot, he already has that measurement.
Setting lash to specs and setting lash to what the motor wants or needs might not be the same setting.