DW10 vs DHX vs DHY Rods

[ally406]

Just out of curiosity while I had all 3 sets together at the same time. From left to right we have DW10, DHX and DHY. When I took the photo I thought the DW10 and DHX rods were the same, but looking at the photo I now think the DW10 is slightly beefier. The DHY on the right is clearly a lot thinner, which backs up it's reputation for throwing rods more readily than the DHX. Does anyone know if it's only physical dimensions that differ between DW10 and XUD rods? Or does the DW10 use some other manufacturing process for added strength? I note a colour difference but that could be down to other factors.

Another interesting thing I found was that the DHX uses slightly different rings and pistons than the DHY and as such they can't be mixed and matched.