So, what happened to my question about hockey games as a worst-case scenario for arena traffic analysis?

From the Board Materials for today's Empire State Development Board Meeting:

At the Directors meeting on June 12, 2014, one commenter informed the Directors that one of his comments had been omitted from the FSEIS [Final Supplemental Environmental Impact Statement] and provided a copy of that comment to the Directors. The comment raised the issue of whether the SEIS should have considered a New York Islanders hockey game at the arena, rather than a Brooklyn Nets game, as the reasonable worst-case scenario in the traffic and transportation analyses. Subsequent investigation by ESD staff determined that this comment had not been included in the FSEIS because ESD’s computer system had quarantined the comment, preventing it from being delivered to the Atlantic Yards mailbox and considered by ESD staff. Nevertheless, in preparing the DSEIS, ESD’s staff and its environmental consultant had considered the issue raised by the commenter and determined that a Nets game, rather than an Islanders game, should be considered the reasonable worst case scenario for analysis purposes, because (i) the Arena is expected to accommodate 1,900 fewer spectators for an Islanders’ hockey game than for a Nets basketball game; (ii) the Arena is located immediately adjacent to the LIRR’s Atlantic Terminal which can be reached from 9 of the railroad’s 10 branches either directly or via a connection at Jamaica (survey data from the April 9, 2013 Nets/Sixers basketball game at the Arena indicate that approximately 51 percent of spectators en route to Long Island after the game traveled by LIRR); and (iii) re‐location of the Islanders to the Arena in Brooklyn is likely to increase the team’s New York City fan base over time.

Well, note that I also re-sent my comment directly to an ESD staffer. And while ESD staff may have considered, that still doesn't mean the Final SEIS was complete.

Sure, re-location to Brooklyn will increase the New York City fan base. But the survey data regarding basketball is not necessarily predictive of hockey fans used to driving to the Nassau Coliseum.

And for the first few years, at least, a good number of people may drive--or at least consider doing so.