current boost amplifier better performance running hot?

[SArepairman]

What does positive saturation voltage specification mean?

I see a curve showing me that under a heavy load and higher temperature the saturation voltage for a particular amplifier is higher.
If I understand this correctly this amplifier will be able to use a greater voltage if it is running hot (120C) and under a heavy load then it does running under a light load at a reasonable temperature.

wtf? I figure it would be the inverse. Why does its saturation voltage increase as the stress it is placed under increases?

[Bertho]

What does positive saturation voltage specification mean?

I guess it refers to the saturation voltage of the active component(s). It is usual that the voltage drop over transistors rises with temperature (bipolar Vce-sat rises or mosfet Rds-on rises). That means that the component's dissipation increases at constant load. Increased dissipation lets the temperature rise further and at some stage you have a run-away process that burns out the component if not compensated.