Description of problem: Today if you want to create a RAID thin pool you first create LVs to be used for the metadata and the data and then run lvconvert on them to make it into a thin pool. It would be good to have at least a single command which supports this for the general use case which utilizes best practice for sane defaults for the user that just want's their thinpool to be placed safely on multiple disks.
2 paths for now exists: -- lvcreate raid LV for data lvcreate raid LV for metadata lvconvert them into thin-pool -- lvcreate thin-pool lvconvert -m+1 data lvconvert -m+1 metadata --- ATM lvm2 is not 'smart' enough for this layouts. Needs to support usage of some smart 'tags' to place those devices just like might have imagine. We may eventually reuse meaning of option '-m+1' for this kind of operation in future to make both LVs (data & metadata) mirrored - but long way to go to reach this without creating completely senseless layouts.