Shia scholar of Hadith Muhammad Baqir al-Behbudi writes in “Ma`rifat al-Hadith” pg.172:

على انك عرفت في بحث الشذوذ عن نظام الامامة ان الأحاديث المروية في النصوص على الأئمة جملة من خبر اللوح وغيره كلها مصنوعة في عهد الغيبة والحيرة وقبلها بقليل فلو كانت هذه النصوص المتوافرة موجوده عند الشيعة اللإمامية لما اختلفوا في معرفة الأئمة هذا الاختلاف الفاضح ولما وقعت الحيرة لأساطين المذهب واركان الحديث سنوات عديدة وكانوا في غنى ان يتسرعوا في تأليف الكتب في اثبات الغيبة وكشف الحيرة عن قلوب الامة بهذه الكثرة
[And you (reader) now know after the research on “al-Shudhudh `an Nizam al-Imamah” that the narrations about the general identity of the Imams such as the narration of the Tablet (1) and others, are all fabricated during the time of al-Ghaybah (2) and al-Hayrah (3) and some short time before it. For if these narrations were available with the Imami Shia, they would not have disagreed so openly and greatly about the identity of the Imams, nor would the biggest personalities and narrators of Hadith have faced much confusion for long years, nor would they have needed to quickly write books proving the Ghaybah to unveil the confusion from the hearts of the nation in such great numbers.]

Footnotes:
(1) Narrations of the Tablet are those when Jabir (ra) walks in on Fatima (ra) and sees a tablet with the names of the Imams on it.
(2) al-Ghaybah is the period of occultation of the Shia 12th Imam when he was never seen nor heard from by anyone except four people and only for a couple of years, then followed by the greater occultation.
(3) al-Hayrah is the great confusion that struck the followers of the Imami branch of Tashayyu` when the news of their Imam stopped reaching them after the death of the fourth emissary and lots of them abandoned the Madhab.