I'd almost bet the trainee is following Oh Ryan, & that can't be good while training. Having deliveries sprinkled in with pickups on a heavy business route is so dumb & very confusing for someone training. Happens on my route a lot. In fact they tried to train 2 people on mine recently, both of which failed miserably, & I believe Oh Ryan was the main culprit. Since I've been doing my route for awhile now, I know how to either A. Run it my way from RDO or 2. Run Oh Ryan/my way from ODO which I started doing a couple weeks back to see if it'd decrease my stop count some.
My advice, switch from ODO to RDO, & I'm with the other drivers on here. Talk to the bid driver of this training route & get input on the best way to run it, & get to know veteran drivers in your hub/center. Much more knowledgeable about delivering than management.