Ten years have elapsed since the first Tobacco Advertising judgment, in which the Court for the first time concluded that the EU legislature had stepped beyond the limits of its competence to harmonize national laws which is granted by the Treaty. However, those subsequently seeking annulment of measures of harmonization have almost all been disappointed. This paper surveys the accumulated case law and finds that the “limits” of EU legislative competence, though of the highest constitutional significance in principle, are in practice imprecisely defined by the Treaty itself with the consequence that the legislative institutions enjoy wide discretion. The pattern has become circular: the Court presents a formula which defines the proper scope of harmonization and which sets out the control exercised by the principles of proportionality and subsidiarity, the EU legislature duly adopts the approved but reliably vague vocabulary and, provided the drafting is well-chosen, the Court has no plausible basis on which to set aside the legislative act. Case law dealing with the limits of EU competence has been converted into no more than a “drafting guide.” The paper shows how many of these deficiencies have been maintained uncritically after the reforms made by the Lisbon Treaty, even though a major part of the reform agenda initiated by the Laeken Declaration was inspired by “competence sensitivity.” Lisbon has instead put most of its reforming faith in a new recruit to competence monitoring - the national parliaments of the Member States. These new arrangements are poorly shaped at the level of detail, but the paper concludes with a largely positive assessment of the intention behind them. In particular they reveal a proper insistence on the need to supplement judicial control, which has become largely ineffective, with fresher political sensitivity to the perils of over-hasty centralization.