I receive a number of questions on apostolic succession. I keep getting them, so I figure I will keep trying to answer the questions about AS until I've done it enough that I don't get anymore questions; or, I'll keep answering them until I don't feel like it.
I've said, in the past, that Apostolic Succession isn't something you need to be a Gnostic or to have "valid" sacraments; some Gnostic groups put a lot of emphasis on the fact that they have it, and a few others put a lot of emphasis on the fact that they don't have it.
The modern ecclesiastical Gnostic movement has appropriated a lot of ecclesiology from its distant orthodox cousins, for better or worse. One interesting notion that many churches have acquired is the Western (e.g. Roman) notion of "sacramental validity" and the necessity of Apostolic Succession for the "valid" administration of sacraments. To my mind, that notion is a baseless one constructed on centuries of Western theological scholasticism. It has no place in the pursuit of Gnosis.
We all know that the lists of Apostolic Succession have holes in them somewhere, the Roman ones usually fall apart around the time of Cardinal Barberini, and the Eastern ones have their chinks too. While the myth of the Historic Episcopate passed down from person to person since the time of the Apostles could possibly be true it certainly isn't probable.
You the Gnostic make the sacrament "valid" by your participation in it. Whether or not you were ordained by someone whose name is on a list of bishops is immaterial to the efficacy of a practice. I don't have any special magic that makes these things more efficacious... well, okay, maybe I'm slightly more charismatic and charming than you are.
As Gnostics we're not looking to become another "successor to the Apostles" but another Christ. Our goal is that eventually we too will know and understand what three things The Living Jesus said to Thomas.
Within the Thomasine tradition, Apostolic Succession is a way of connecting with the past and, in a subversive way, of liberating the message of The Living Jesus from something that has become corrupted by its long association with power.
So, does apostolic succession matter? I don't really know. I do know that the consecration, as an initiatory experience, was meaningful and transformative for me. It has been a source of help to me over the years in the struggle for Gnosis. Also, Chrism smells good, so it was nice that I had a bunch of it poured on my head.