Back in the day (1960s) I read an article in Mechanics Illustrated that you could make a coolant recovery system using a Buick rad cap. This had a check valve in the bottom that opened to allow coolant to be sucked back into the rad through the overflow in the neck when the pressure dropped. I put one on my '68 Camaro, using an aftermarket windshield washer bottle as the overflow tank with the hose running down to the bottom of it. Nowadays all cars have coolant recovery systems for environmental reasons. I just don't understand the need for the tank to be pressurized, unless it's to reduce coolant bowing out in the case of severe overheating.
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1992 745, >500k km