For this tournament it is banned. Not because of Zjiin's match, but because it seems to me that it reduces the game to chain-grabbing.
I knew the Zelgadis vs Eddie match would come up. That's a classic example of what made pipes ******** in Melee. Fox was pretty much the only viable character on that stage. The only difference between that situation and this one is that waveshining actually took a little bit of skill (i never mastered it myself) but falco chain-grabbing is hella easy.
Ultimately, this conversation boils down to what your philosophy is on what makes a stage ban-worthy. Sirlin is wise, but he is not Jesus. His suggestions on bans are important to understand, but ultimately, the community has to decide what are the core elements of the competitive version of the game we play, and then structure our tournaments to support those elements.
As a small time TO, I can get away with some minor experimentation in terms of stage selections. If you (the collective community) told me my stage selections were ********, I would obviously be going in the wrong direction if I wanted to be a part of your community. This kind of experimentation can help us understand what stages belong on our banned list long-term.
We have a few options to choose from to help us understand what needs banned and what doesn't. One option is to not ban anything at all, and see if the game is reduced to one tactic or one stage or one character. Another option is to selectively ban things slowly to try out different sets of stages, and then see how that ruleset works for us. If we stumble across a combination that seems to result in the "optimal" (as decided by the community, not by some impartial rule Dave Sirlin wrote, wise though he may be) competitive environment, then we have improved upon our situation as a community, and given ourselves a much more positive competitive gaming experience.
I'm ok with either option, but the community as a whole has already started banning things selectively. I have very good tournament players tell me that Hanenbow should absolutely be banned, and another group of players saying it's a completely acceptable counterpick. I've seen Pictochat on banned lists and neutral lists. I've seen PS2 on both banned and neutral lists. I prefer to remove Lylat from the neutral list and put it in as a counterpick, but for this tourney, it's a neutral
Because the generally accepted method of running a Brawl tourney so far is to ban some stages, I've made a list that seems pretty balanced to me. I am comfortable with some of you disagreeing with my stage lists. Brawl is far too new to have a completely worked out list already (much like the Tier list, which shouldn't be decided on for another 8-12 months). TO's have to make decisions, and I made the best ones I know how to make at this point. For every negative comment I've had from someone about my stage choices, I've also had positive comments saying that my choices made complete sense.
Either way, we're going with this list for now.