Fuel Oil to Operate Boiler Systems

I just received the following question and was wondering if anyone had any information about it:
"During the time when barrel prices were achieving record high prices many companies were investing in new pump and heater sets to make the switch from #2 fuel oil to the significantly cheaper #6 fuel oil to operate boiler systems. I would be interested to find out how much this trend has slowed down or is the memory still fresh enough that businesses are still making this capital investment."

Any thoughts?