First of all, we need to realise that the entire Mahabharatha is a literary representation of actual events that happened in ancient India. There was a war between two clans, between armies led by two groups of kings and princes who were brothers in relation, and one group (Pandavas) completely annihilated the other (Kauravas).
Vedavyasa, a contemporary of the time when the war was fought, was also a great scholar: prior to him, all Vedas were one set of complicated verses. Remember that the Samskrita language and grammar used in the Vedas is completely different, ancient and difficult than the language and grammar that is used in Mahabharatha: by this we can say with some confidence that the language that was used in Mahabharatha was the language that was spoken during those days. For an average person of average intelligence living in those days, the language used in the Vedas can be expected to be quite difficult.
Now, Vedavyasa learned the Vedas from his father Parashara muni, and mastered all the Vedas in a very young age. In the process, he also realised that it will be a humungous task for anyone to completely memorise the whole Vedas in one lifetime. So, he took in four eminent and bright young scholars, Paila, Vaishampayana, Jaimini and Sumanthu, divided the Vedas (Vyasa means to divide) based on their content and nature of verses into Rigveda (which contained mostly verses in metre), Yajurveda (which contained mostly prose hymns), Samaveda (which contained verses which were intended to be sung), and Atharvanaveda (which was a collection of spells and incantations, apotropaic charms and speculative hymns), and assigned one Veda to one disciple each: Rigveda to Paila, Yajurveda to Vaishampayana, Samaveda to Jaimini and Atharvanaveda to Sumanthu. With the Vedas divided, it became relatively easy to conserve the knowledge contained in them: we can easily say that, if the Vedas are surviving today, it is heavily due to the efforts of this great sage, Vedavyasa.
This alone can give us a fair picture of the genius of Vedavyasa: to be able to classify something as huge as the Vedas, one must have complete and thorough knowledge of them in its entirity.
At the same time, the events leading to the Mahabharatha war were happening.
go to next page to know how Krishna stopped time