Bootloader and partition stuff

[Bappy1988]

So, I tried to follow devendor's instructions very closely, but had all sorts of trouble trying to get a bootloader installed manually. errors like 'cannot get cannonical path for /cow' or '/dev/mmcblk0p2' etc.

I ended up going back to the devices, splatting the partitions and re-creating them without lvm2.
I created 3 primary partitions on the internal device, a 512MB vfat partition for EFI (wasteful but the ubuntu installer thought 134MB wasn't enough? ), a 1GB partition for /boot and most of the rest for / (I left some space unallocated as I read somewhere that SSDs will use unallocated space as 'spare blocks' in the case of wear)

I have a 128GB microsd card permanently inserted so have mounted that whole thing as /home

I then got the ubuntu live cd to install normally, but manually selected the partitions and it installed grub without any trouble.

So I am left with the question, is it really necessary to mess about with bootloaders? the livecd worked without issue for me...

Was this just so that we can get the / partition created as a logical volume and not a primary partition? Does this have something to do with TPM and encryption?

Another vaguely related subject. I noted that a couple of others have had issues with file system errors. I remember reading somewhere that journalling on an MMC device is a no-no for device wear and tends to flag many errors. Google even added a -O ^has_journal switch to mkfs to disable it for their embedded stuff. I tried that, but the ubuntu installer interprets ext4 without journal as ext2, then fails to mount it, so I've actually gone with ext2 as the filesystem on all my volumes (except EFI) and let the installer format them. Just thought it worth noting somewhere in case it's useful to others.

I'm bringing this stuff up, as I would find some more background into the recommendations really helpful for my learning.