What Imâm al-Shâfi‘î said does not mean that everyone who sees a sahîh hadîth should say “This is the madhhab of al-Shâfi‘î,” applying the purely external or apparent meaning of his statement. What he said most certainly applies only to such a person as has the rank of ijtihâd in the madhhab. It is a condition for such a person that he be firmly convinced that either Imâm al-Shâfi‘î was unaware of this hadîth or he was unaware of its authenticity. And this is possible only after having researched all the books of al-Shâfi‘î and similar other books of the companions of al-Shâfi‘î, those who took knowledge from him and others similar to them. This is indeed a difficult condition to fulfill. Few are those who measure upto this standard in our times.  What we have explained has been made conditional because Imâm al-Shâfi‘î had abandoned acting purely on the external meaning of many hadîths, which he declared and knew. However, he established proofs for criticism of the hadîth or its abrogation or specific circumstances or interpretation and so forth. Shaykh Abu ‘Amr [Ibn al-Salâh] said: “It is no trivial matter to act according to the apparent meaning of what Imâm al-Shâfi‘î said. For it is not permissible for every faqîh – let alone a layman (‘âmmî) – to act independently with what he takes to be a proof from the hadîth… Therefore, whoever among the Shâfi‘îs finds a hadîth that contradicts his School must examine whether he is absolutely accomplished in all the disciplines of ijtihâd, or in that particular topic, or specific question. [If he is,] then he has the right to apply it independently. If he is not, but finds that contravening the hadîth bears too heavily upon him–after having researched it and found no justification for contravening it–then he may apply it if another independent Imâm other than al-Shâfi‘î applies it. This is a good excuse for him to leave the madhhab of his Imâm in such a case.” 
 See, in particular, Shaykh al-Islâm Taqî al-Dîn al-Subkî’s Ma‘nâ Qawl al-Imâmal-Muttalibî Idhâ Sahha al-Hadîthu Fahuwa Madhhabî; Ibn al-Salâh’s Adab al-Muftî waal-Mustaftî; and the first volume of al-Nawawî’s al-Majm‘.
 I.e. al-Nawawî’s times, a fortiori ours. Among those who lived in al-Nawawî’s century were al-Fakhr al-Râzî, Ibn al-Salâh, al-Mundhirî, Ibn ‘Abd al-Salâm, al-Qurtubî, Ibn al-Munayyir, Ibn al-Qattân, al- Diyâ’ al-Maqdisî, Ibn Qudâma, and Ibn Daqîq al-‘îd!
 Al-Nawawî, al-Majm‘ Sharh al-Muhadhdhab (1:64), citing Ibn al-Salâh’s Fatâwâ waMasâ’il (1:54, 1:58-59). Cf. al-Tahânawî, I‘lâ’ al-Sunan (2:290-291).