Very good question: WLTP has just a number for you.
PHEVs may not be a good idea depending on your driving style. There should be more discussion about what type of engine is the correct one for you before buying. Do you drive enough motorway regularly that a diesel would make sense? Do you drive shorter distances but you cannot charge? Can you charge but you sometimes need more range? Maybe even a PHEV diesel would make sense, but that is a type of vehicle that was rare and is now even rarer.
Technology was improved a lot over the last decades. If you'd record the WLTP tests you could maybe build a system which would accurately calculate your fuel usage for your type of driving and define if a PHEV or a diesel would make any sense for you.
PHEVs may not be a good idea depending on your driving style. There should be more discussion about what type of engine is the correct one for you before buying. Do you drive enough motorway regularly that a diesel would make sense? Do you drive shorter distances but you cannot charge? Can you charge but you sometimes need more range? Maybe even a PHEV diesel would make sense, but that is a type of vehicle that was rare and is now even rarer.
Technology was improved a lot over the last decades. If you'd record the WLTP tests you could maybe build a system which would accurately calculate your fuel usage for your type of driving and define if a PHEV or a diesel would make any sense for you.