Although, I am beginnng to think there is no way that the 79 TOS episodes, the 22 TAS episodes AND the hundreds of TOS novels could ALL happen in only 5 years.
Although there's always the interpretation Roddenberry hinted at in his TMP novelization prologue, that the episodes and stories we see are dramatizations based on the real experiences of Kirk and his crew. So while many of them may be adaptations of actual events, others may be fictional accounts. Kind of like how Desilu Playhouse
did an adaptation of the book The Untouchables
which was supposedly based on the historical account of Elliot Ness and his role in bringing down Al Capone (although it's now known that book was mostly fictionalized), and then Desilu spun it off into a weekly television series about Ness and the Untouchables having completely fictitious adventures.