There were several different reasons for the practice. The two biggest were likely for recognition and acceptance (who would read something by Jonathan the Acolyte to Simon who was the scribe for James?).
The second was for continuity. Particularly in the Talmudic tradition, argument from the style of an earlier scholar was not just common, but honored. For "argument in the style of" to work, several things were necessary.
First, all the participants needed to be intimately familar with the full body of writings of the person the new work would be attributed to. Second, it was recognized among the group that it was not the person the new work was attributed to that was speaking, but "An Argument in the style of".
The third point is very important. The new writing was judges under two seperate criteria. It must stand up in both areas or it waould fail.
It must actually be "in the style of". If the audience did not se a continuity of thought, manner, presentation, logic and content, then the argument, no matter how valid, would be rejected. Second, the new writing must be original yet consistent. It must be capable of being supported, even if all others disagreed with it.
Since both of these conditions were simply unspoken, works that passed this rigorous filtering entered the overall body of work under the attribution of the person it was attributed to as opposed to the author. At the time, it's likely that many even outside the vetting body were aware of the actual state of affairs, but since it was common practice, it would not be comment or noted.
As time passed and the actual people with first hand knowledge of the event died, the details that led to the attribution, never formally documented in the first place, would be forgotten.
Aslan is not a Tame Lion
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