Ibn al-Qayyim himself ruled the ḥadith weak in Zad al-Maʿād, and I have treated the matter at length in Takhreej Sifat Salat al-Nabi ﷺ and in Daʿīf Abī Dāwūd 175, in a manner that leaves no room for doubt as to its infirmity. In brief: the report is transmitted by Muḥammad ibn ʿAjlān from ʿĀmir ibn ʿAbd Allāh ibn al-Zubayr. Ibn ʿAjlān’s reliability is disputed, and four trustworthy narrators relate the ḥadith from him without the words, “he would not move it.” Two sound narrators also transmit it from ʿĀmir without that clause. This establishes that the addition is anomalous and weak. A further indication of its fragility is that Muslim records the ḥadith (2/90) through the very same Ibn ʿAjlān yet omits the phrase altogether. All of this escaped the annotator of Zad al-Maʿād; taking the chain at face value he rated the ḥadith ḥasan and even strengthened it in his notes on Sharḥ al-Sunnah (3/178). Although he immediately cited—and authenticated—the ḥadith of Waʾil that affirms movement, he made no attempt to reconcile the two texts, as though the legal implication were of no concern to him; consequently, he does not move his finger in the tashahhud!

I would like to add a new observation on the subject. Shaykh Aḥmad al-Ghumārī, in his recently published work al-Hidāyah fī Takhreej Aḥādīth al-Bidāyah (Bidāyat al-Mujtahid), 3/136–140, also weakens the ḥadith of Waʾil, contending that the word “moving” is the insertion of certain transmitters, for most versions mention only pointing, not movement.

During my last ʿumrah trip, in early Jumādā al-Ūlā 1408 AH, a student in Jeddah handed me a photocopied paper from the Sudanese periodical Majallat al-Istijābah entitled al-Bushrā fī Shudhūdh Taḥrīk al-Isbaʿ fī al-Tashahhud wa Thubūt al-Ishārah, authored by a Yemeni student. He generally concurs with Shaykh al-Ghumārī in the point just mentioned, but distinguishes himself by giving a wide-ranging documentation of the reports on pointing attributed to various Companions and their numerous chains of transmission.