Bonifacio was the worst baserunner on the team last year... the fastest but so bad at reading the situation that he usually got himself out. Navaro may have only made it to first but he was SAFE at first and that's all I care about.
I dont consider it a slump. This is just the way he hits. Every once in awhile he will sparkle and hit a few HR and bring the average up, but generally this is how he is most of the time,