Can a defendant complain of his counsel's inadequacy or ineffectiveness at trial on appeal?

A defendant cannot be heard on appeal to complain of his counsel's inadequacy or ineffectiveness at trial if defendant is advised by the court of possible problems concerning that attorney's competence and he knowingly, intelligently, and voluntarily choses to proceed with that particular attorney. A contrary rule would impermissibly allow a defendant "an automatic right to reversal on appeal should the defense or defenses at trial fail." (People v. Cook, supra, 13 Cal.3d at p. 673, fn. 10, 119 Cal.Rptr. 500, 532 P.2d 148.)