Governor Charlie Baker said Thursday morning on GBH News’ Boston Public Radio that he was “pissed off” about the state’s vaccination finder website crashing as Massachusetts expanded eligibility to an additional one million residents. The incident was just the latest bump in the state’s troubled vaccine rollout, which Harvard Kennedy School professor Graham Allison gave an ‘F’ grade in comparison to other states last week. But this week, he upgraded his rating to a ‘C.’ Allison, who previously served as the Assistant Secretary of Defense, joined Jim Braude to explain what changed and where he still sees room for improvement.