Changing marathon training schedules

I might be insane. I am about 5 weeks from the Buffalo marathon, and I am changing training schedules. I have been using the Hal Higdon intermediate II schedule, but running using priciples from Phil Maffetone. I haven’t gotten much faster. I have seemed to have plateaud. I am training in martial arts class 5 days a week, and have been running 5 days a week. I feel tired and sore most of of the time. I am going to try the schedule from the 4 Months To A 4 Hour Marathon. I am planning on using the 4:30 schedule for now. There are only four days, and two of those are short jogs. The other two runs are a long run, and another short fast run. I think this will alow my body more recovery time, and maybe allow me to get a little faster. It’s worth a shot. But this close to the marthon, I am getting close to tapering anyway.