thats a good question . ive asked that of vets here many times .again you get people in both camps . but the guys i really listen to basically say it makes no difference , especially at the level of i.u im taking and above (5i.u e.d)
and to answer your question about 5 on / 2 off split , if i may . this has no benefit other than to make it cheaper . in fact as you suspect it is better to maintain a e.d protocol