I didn't say that. But you also can't claim that NO ONE is worth having those merits and should be set to 0. Without going through every post ever made and re-evaluating everything (completely unfeasible) I don't think it's possible to come up with a totally fair formula. Just to make this clear - I would be fine with 0 merits. I don't see any significance in the starting number at all. I'm saying that if theymos had started everyone with 0 the moaning would be just as loud.
Jr. Member -> Member 0-10
Member -> Full Member 0-90
Full Member -> Sr. Member 0-150
Sr. Member -> Hero Member 0-250
Hero Member -> Legendary 0-500
Legendary 0-0
By using the system like this, no-one would be born with a "grandparent" advantage, and at the same time no-one would have the right to feel "cheated".
Win/win
This scheme wouldn't work when those old members need to get to the next rank after their first rank-up. Sr. Member who started at zero earns 250 and becomes a Hero Member. Then what?
This is a status quo scenario. Building up to the next rank a person who went from Sr. Member to Legendary would need 750 merits from the introduction of the merit system. It would mean exactly the same in term of rank progression as the current system, but it would separate the good legendaries and heroes from the no good.
By using the system like this, no-one would be born with a "grandparent" advantage, and at the same time no-one would have the right to feel "cheated".
Your phraseology of "grandparent advantage" causes a pretty strong inference that you do not understand the basic fairness that is meant to come from the employment of such a principle. Grandfather clauses are not meant to cause injustices, disadvantage, unfairness or exploitation of new users in favor of old but instead are meant to allow a fair transition in systems that does not prejudice prior membership or prior members' reliance on earlier terms.. it is a kind of basic transitional remedy that is used in a lot of places to cause fairness rather than unfairness.
You fail to see that not all grandparents are worthy of grandparent advantage. That being said, I think you fail to see that my suggestion won’t take any advantages from such. Quite the opposite actually. It will make the worthy people with great seniority stand out even more.