Sheiko newbie: What no SDLs or RDLs. And what's with the chains?

Hi,

I'm new to Sheiko training and after looking through some of the programmings I notice there are no SDLs or RDLs included unless I missed them.

I'm just curious why these deadlift variants aren't included and should I keep them out of my program?

I also noticed there are many variants of deadlifts using chains but only one using bands.

What are the benefits of using chains for deadlifting and can these simply be swapped out for bands or would I be better off buying some chains for my local gym?

TIA

Sheiko uses a deadlift variation with a similar effect. He calls is a deadlift from center block.

You can use bands too. Chains could be a little easier to set up though.