In the "Enterprise" series final we saw him watching old events of the ship Enterprise to help him make a choice on what to do about Admiral Pressman. Since they did that why not go all "Observer" on the Trek universe and make it all pone big holodeck adventure after adventure that Riker has created to learn more lessons on how to deal with stuff. Each time you watch a old episode you can have a "Where's Waldo" moment where you try and spot Riker in the show. This would also explain any canon issues people would have with any show since it would be Riker not knowing the details or simply making small mistakes in his holodeck re-creations.
Jason
Jason