Thank you for these thoughts. The suggestions of Andrew about how to make an appeal will probably get me unblocked.
But, in the first place, I'm not sure if I was blocked correctly. I was told in my last request for unblock that "the same person and only that one person may press the keys on the keyboard". Is this part of the policy regarding the role accounts? To my knowledge, it would be only here where one may find info about this notion:
http://meta.wikimedia.org/wiki/Role_account
And given my personal case, it looks like it needs some elaboration, my impression is that it leaves too much space for personal interpretations. Also it should be more visible, in the times I was active in various Wikimedia projects, I never came across it, to give a thought about what I'm doing. And I spent some time on meta.wm to learn how to organize a new Wikipedia. Probably this is because there are few such cases, unlike the opposite context of sockpuppetry, about which it is impossible to spend some days in Wikipedia and not know about it. I remembered the case of this account (I found it somewhere in statements at the RfC about paid editing) apparently not sanctioned as an official role acount (at least I did not see it in that meta.wm list):
http://en.wikipedia.org/wiki/User:Nttc
A lot of people probably saw it and I saw no sign on somebody rising this issue.
My interpretation of the phrase "Any other accounts with multiple users are likely to be blocked." (from that meta.wm page) is that an account with uncertain practices (it does not state it is a role account, from the edits it results there is no awareness about this thing) should be warned first about this rule, to decide what to do. Do you want to be a role account? Please give us the reasons for accepting you as such. If not, please get individual or abandon this account, otherwise we will certainly block you. Besides the lack of awareness about this notion, I would state a lack of intended noxiousness (unlike the sockpuppetry) as a reason for a first warning (I'm not sure what bad things can one do in a case like mine or the above Nttc, though I don't know what else might happen in sensibly different situations).
This if my case is indeed under the current definition of a role account. Plus that my case is a really old issue, I find an indefblock way over the top. Sincerely, I didn't like at all the way I was blocked and my conscience does not let me so easy go through Andrew's suggestion.
Desiphral