I have played D&D since the early 80s, played every version. I always roll HP for monsters. I will bump them up more in game if the party is steam rolling the encounters, and lower them if they are taking too much damage and using too many resources. To tell me that all goblins have 7 hp is laughable. They have a range.
The conversation given above regarding max DAMAGE does not equate to Max Hit points. IF I handed down max damage for every hit that would be really craptastically unfair.