If you thought the last Democratic mayoral debate was thin on transportation issues, you could be forgiven for thinking that the issue didn’t come up at all during last night’s event. Blink, and you might have missed it. Like last time, transit was relegated to the lightning round, and thin questions from the moderators didn’t elicit much information from the candidates.

At the previous debate, all the candidates had MetroCards in their pockets but we learned last night that they are, for the most part, infrequent straphangers: Thompson said he had last taken the subway on Monday, while de Blasio and Weiner rode the train last week; Liu and Quinn hadn’t swiped a MetroCard in about two weeks.

On the subject of the MTA, Liu said he had “gone after very powerful interests,” repeating the myth created by disgraced former Comptroller Alan Hevesi that the authority keeps “two sets of books” to obscure its finances from the public.

The candidates all rejected the idea of road tests and licenses for cyclists. Weiner boldly added that cyclists should yield to senior citizens, and Liu said that cyclists should wear helmets. (At the last debate, Liu supported mandatory helmets for “city-sponsored programs” like bike-share; Thompson supported compulsory helmets, while Quinn, de Blasio, and Weiner opposed a helmet law.)

It was a lightning round question from WNBC’s David Ushery that most clearly revealed the vacuousness of mainstream discourse on transportation. Ushery asked the candidates if they support tolls on the East River bridges, without mentioning whether the funds would be dedicated to improved transit, or any of the upsides that come from pricing roads. Faced with this question, the candidates were unanimous in their opposition to East River bridge tolls; Liu added that he only supports tolls that exempt city residents from paying the charge.

Profiles in courage, all of them.