On May 17, the 80-plus Arlington-Belmont High School crew team members will gather together on the first anniversary of a shocking, completely unforeseen hurdle. A team-building activity — part reflection, part appreciation — will emphasize the human element of what transpired. As quickly as the program lost 11 boats to theft, they rallied and rebuilt at an even faster clip. “Settling back in and getting restarted from where we were before, I think it’s come a long way,” said Belmont…