Please advise, but [Grammar Girl](http://www.quickanddirtytips.com/education/grammar/verbs-sandwiched-between-singular-and-plural-nouns) opines that the problem here is 'false attraction to a predicate noun'. I excerpt the fundaments:

>Although this problem may seem complicated, it’s really not. It’s as simple as this: the verb agrees with the subject (2)***, not the predicate noun. - See more at: http://www.quickanddirtytips.com/education/grammar/verbs-sandwiched-between-singular-and-plural-nouns#sthash.y0KLwgtk.dpuf

>Dorothy, don’t pay attention to the man behind the curtain, meaning don’t be distracted by the predicate noun. One grammar source calls this problem “false attraction to a predicate noun” (3). - See more at: http://www.quickanddirtytips.com/education/grammar/verbs-sandwiched-between-singular-and-plural-nouns#sthash.y0KLwgtk.dpuf

***The (2) and (3) refer to external references on p 2 of 2 of Grammar Girl's article.