Well I am biased in that matter since I find adrenaline a nuisance.
So I would like to "punish" it's usage by for example multiplying that factor 8 with (#adren shots / (playtime*0.5)) because then you surely are abusing that, playtime in minutes then. (a minimum of 1 is required, don't want to go below 8).
As such you still can use adrenaline without a problem, only not too often.