Just a quick question to make me sleep well tonight… 
I’ve read up on several shadow tutorials, but all of them failed to explain to my tired flu-ridden mind - why do I need to extrude the shadow volume into infinity? Why not just make it exit the far clipping plane?
If you make it exit the far clip plane, you wont be able to cap the far end of the volume.
If you dont extrude it to “infinity”, you may have cases where the shadow for an oject just stops and is clearly visible stopping.
Aah… The capping, yes. Thank you!