When was Dayaqot – R. Shmuel Ben Meir's Grammatical Treatise – Written?

Rashbam — R. Shmuel ben Meir — compiled a grammatical treatise, Dayaqot, of which only a single manuscript has survived. The first part of this treatise is a grammar book of eight chapters, while its second part is a grammatical commentary to the Bible, which ends abruptly at Genesis 7:5. A new edition of Dayaqot was published by Ronella Merdler in the year 1999. A number of scholars (Yom Tov Stein, Henoch Yalon, Ronella Merdler) have surmised that Dayaqot was compiled by Rashbam late in life, after he had completed his Commentary to the Pentateuch, and they have presented some evidence supporting their position. A close examination of the evidence leads, I believe, to the opposite conclusion: a study of four topics discussed in Rashbam's Torah Commentary as well as in Dayaqot indicates that Dayaqot preceded the Torah Commentary and was, therefore, compiled in the author's youth. In an appendix, the article tells of the rediscovery of the manuscript of the first edition of Dayaqot, redacted by Yom Tov Stein.