That's a very fast reduction schedule at 1mg every two weeks, especially under 5mg. Most often reductions are made every 4 - 8 weeks to avoid pain, give the PMR time to resolve, and give your body time to resume its own cortisol production. Your doctor's suggestion to return to 5mg and then alternate 5mg with 4mg would give a reduction of .5mg rather than 1mg, which makes sense if you have pain returning. Reducing by smaller increments and taking it more slowly is usually better.