Who is Roy Bland from Tinker, Tailor, Soldier, Spy and what is their importance?

Roy Bland was one of Smiley's recruits. He worked his way through school and attended training sessions at the Nursery during his off time from school. His cover was as a leftist intellectual, and he went onto accept an economics teaching position at the University of Poznan, after which he went onto teach at the Budapest Academy of Sciences. Bland also taught in Prague, Sofia and Kiev.