As for the hadith of Anas reported by Abū Dāwūd (1):
“I saw the Messenger of Allah (may Allah bless him and grant him peace) performing ablution while wearing a turban of red, patterned cloth. He slipped his hand beneath the turban and wiped the front of his head without undoing the turban.”
What Anas meant by this (2) was that the Prophet (may Allah bless him and grant him peace) did not undo his turban so as to touch (3) all his hair. He did not deny that he completed the wiping over the turban. Al-Mughīra ibn Shuʿba and others explicitly reported this (4), so Anas’s silence on the matter does not imply its denial.
The Messenger of Allah (may Allah bless him and grant him peace) never performed ablution without rinsing his mouth and drawing water into his nose. No report records him omitting this even once (5). Likewise, he always performed the acts of ablution in their proper sequence and without interruption, never departing from this even once.
He would sometimes wipe over his head, sometimes over his turban (6), and over the front of his head
(1) Recorded by Abū Dāwūd (147), Ibn Mājah (564), al-Hākim (1/169), and al-Bayhaqī (1/60). After giving its chain of transmission, al-Bukhārī said in al-Tārīkh al-Kabīr (6/28): “It is not authentic.” Likewise, al-Hākim cited it not as a supplementary report, but to draw attention to an unusual wording: that he wiped part of his head. Al-Dhahabī said: “If authentic, it would indicate wiping part of the head.” The hadith was judged weak by Ibn al-Mulaqqin in al-Badr al-Munīr (1/676), Ibn Hajar in al-Talkhīs (1/142), and al-Albānī in Da‘īf Abī Dāwūd—al-Umm (1/46–48).
(2) Bihi (“by this”) is absent from ص and ك.
(3) ك, ع, مب read min (“of/from”), probably a scribal corruption. ن reads mash (“wiping”).
(4) This refers to the hadith of al-Mughīra ibn Shu‘ba recorded by Muslim (274/81–83): “The Messenger of Allah (may Allah bless him and grant him peace) stayed behind, and I stayed behind with him. When he had relieved himself, he asked, ‘Do you have water?’ I brought him a vessel of water, and he wiped the front of his head, over his turban, and over his leather socks…” The hadith continues.
(5) ك adds al-batta (“at all”) after this.
(6) “And sometimes over his turban” is omitted from ص owing to a scribal eye-skip.