Grading of the chain: This chain is very weak (da'if jiddan). Al-Dhahabi said in his "Talkhis": al-'Awfi (Muhammad bin 'Abd al-'Aziz) is unanimously regarded as weak, Bakkar is not reliable, and the hadith is "wahi munkar". Abu al-Zinad refers to "'Abd Allah bin Dhakwan".

Reference / Source: Al-Bayhaqi narrated it in "Shu'ab al-Iman" (2092) from Abu 'Abd Allah al-Hakim, with this same chain.

Reference / Source: Abu 'Ubayd narrated it in abridged form in "Fada'il al-Qur'an" (p. 350) from Yusuf bin al-Ghariq, from Muhammad bin 'Abd al-'Aziz, confining himself to its beginning. He dropped Abu al-Zinad from its chain.
Criticism: Yusuf bin al-Ghariq is "munkar al-hadith", and Abu al-Fath al-Azdi (as stated in "Mizan al-I'tidal") accused him of lying. This hadith will come later at number (2990) via 'Abd al-Malik al-Raqashi from Bakkar.

Meaning of al-tafkhim (al-Suyuti): Jalal al-Din al-Suyuti mentioned in "al-Itqan fi 'Ulum al-Qur'an" (at the end of the thirtieth category) five views of the scholars on the meaning of "tafkhim". The fifth is that tafkhim means giving the middle letters of words a damma or kasra vowel in the disputed places, rather than making them sukun, because that makes them fuller and weightier.

Statement of al-Dani: Then he said: al-Dani said that it has likewise been explained from Ibn 'Abbas. Then he gave the chain (Ibn Khaqan, al-Kisa'i, Sulayman, al-Zuhri) that Ibn 'Abbas said: "The Qur'an was revealed with tathqil (heaviness) and tafkhim, such as his saying 'al-jumu'ah' and similar instances of tathqil." Then he cited al-Hakim's marfu' hadith from Zayd bin Thabit: "The Qur'an was revealed with tafkhim."

Explanation and support: One of its narrators, Muhammad bin Muqatil (al-Marwazi al-Kisa'i), said: I heard 'Ammar (Ibn 'Abd al-Malik) recite ﴿عُذُرًا أو نُذُرًا﴾ and ﴿الصُّدُفَينِ﴾, that is, with a vowel on the middle letter. He said: This is supported by the statement of Abu 'Ubaydah: "The people of the Hijaz pronounce all speech with tafkhim (vowelling) except one word, 'ashrah', which they pronounce with sukun, while the people of Najd leave tafkhim in speech except for this word, which they pronounce 'ashirah' (with kasra)." Al-Dani said: This view is the most fitting in explaining the report. This is summarised from "Jamal al-Qurra'" by al-Sakhawi (p. 607-608).

Statement of al-Halimi: It has also been said that the meaning of tafkhim (as al-Halimi said) is that the Qur'an should be recited in the manner of men, and the voice should not be softened with it so that it becomes like the speech of women. And Allah knows best. Al-Bayhaqi transmitted this from him.