‘Langston Walker vs. Demetrius Bell at left tackle. There are those inside the Bills’ hierarchy that believe the more athletic Bell would be a wiser choice to start the season opener at New England over the more experienced Walker. Bell, a seventh-round pick in 2008, was making huge strides until suffering a back injury last Monday. He should be back at practice this week. Walker didn’t help his cause against Pittsburgh, struggling to block NFL Defensive Player of the Year James Harrison and picking up a holding call.’