I've been using btrfs on Ubuntu 12.10 for both / and /home for several weeks. Through out the time I've come to the conclusion that ext4 performs better on my system and I'd like to switch back however I've found no easy way of converting both my btrfs partitions to ext4.
Today I've come up with an idea however I'm not sure how safe it is: I'm going to boot from a live environment and shrink my home partition. On the newly created space I'm going to tar my / and /home, reformat the old partitions and finally untar back onto the new ext4 partitions and update grub.
Technically this should be safe however I'm sure that there's some quirk that needs to be done after the whole process which I'm not aware of.
How safe is the process described above and is there a better way of doing it?