Lethal Tempo Usage Stats

Disclaimer: This thought occurred to me while playing my beloved Azir (mid).

Currently lethal tempo's stats are displayed as "active time" in the game. Am I the only one who thinks it would provide better feedback if it displayed the amount of extra damage you deal while it is active (i.e. [Total damage dealt while active] - [damage you'd have dealt w/o lethal tempo AS buff])?

I mean, I can activate lethal tempo all day long by poking champs (which will display in-game & post-game as a high amount of active time), but if I don't deal any damage while it's active then I'm not making efficient use of it and could weigh that feedback against other rune choices.