What is the impact of a defense counsel's failure to request specific instructions for a jury?

"Defense counsel's failure to request specific instructions may be overlooked where the prosecutor's misconduct is so prejudicial that no instruction could mitigate its effects"; but "in less egregious cases, the failure to request specific instructions before the jury retires will limit the defense's ability to complain about the relative lack of curative measures for the first time on appeal." United States v. Melendez, 57 F.3d 238, 242 (2d Cir.1995). This is one of those "less egregious cases." The government never relied upon the challenged testimony, and a curative instruction could easily have done more harm than good by focusing the jurors on two allusive references that they otherwise might have missed or construed as innocuous.