Yet Another Bleeding Problem...
The Summit catalog carries reinforced ones (stainless sleeving around rubber) , yes it can be a problem. Have someone step on your brakes and watch the hoses flex! But I think you have air trapped in the system somewhere. I would look at the front calipers. Get a large c clamp and pull the passengers side caliper, clamp the piston into the caliper with the clamp. Now try bleeding it with the bleeder at the highest point. Put it back together and repeat on the other side.