How have courts dealt with the issue of ineffective assistance on appeal?

^14. For the first time in his reply brief, defendant asserts that if we find forfeiture, then trial counsel's performance was deficient and thereby denied defendant his constitutional right to the effective assistance of counsel. "It is rarely appropriate to resolve an ineffective assistance claim on direct appeal [citation]; we certainly will not do so where, as here, the claim is omitted from the opening brief and thus waived [citations]." (People v. Duff (2014) 58 Cal.4th 527, 550, fn. 9.)