The problem with the terminology focusing on the centre tap, real or virtual, is that folks then get thinking it's the centre tap that's the important thing here, which seems to be putting 'the cart before the horse'. As I see it, what's important is that the heater circuit gets balanced and referenced.
Here's an example of confusion that may have been caused by the 'centre tap' terminology Is a PT secondary center tap a must? - The Amp Garage
The issue being that if the heater circuit loses its 0V reference and a tube short pulls it up towards HT, then the heater-cathode insulation of every tube in that circuit may be damaged.
To avoid the risk of transformer etc damage, the correct value and type of fusing must be used of course, but that's a fundamental (if often ignored) aspect of amp ownership anyway.