Bikemobile,The only way both tires COULD turn forward together is with the transmission in neutral.
In park, the driveshaft will be locked solid. If you jacked it up snd turned the passenger side wheel forward the spider gears in the differential would spin the drivers side wheel the opposite DIFFERENTIAL direction.
As I said before, some LS diffs have spring pressure holding the clutch plates together. These are “tight” versions that are always on but allow slip for turning.
The dana LS is a “loose” LS that allows the spider gears and clutches to slip until a certain amount of slippage “activates” the friction surface on the clutches and locks the diff which gives you equal wheel speed left to right.
Do these "loose" LSD's last longer than traditional LSD's? Perhaps due to less wear and tear on the clutch plates?