I find it odd that rooting via TWRP did NOT work....
Typically custom ROMs have supersu (and its required binaries) already installed and ready to "rock and roll" so-to-speak, so trying to root a custom ROM is kinda pointless [usually] ....
Correct. So, I am not sure why TWRP did not help in this case. I tried the rooting step before I installed Blisspop (I was completely stock at that stage). One of the prerequisite of Blisspop was that you have to be rooted.
just try installing Su from the play store like any other app, If TWRP laid the ground work and you had a positive result with root checker then when you install SU as a normal app and open it, it should ask you if you want to upgrade the binaries. You can always get the SU zip file and flash it in TWRP as well.
I don't have the phone with my physically now. But I will try this next time - getting it from playstore.
Downloading the SuperSU zip and trying to flash it in TWRP - well I did that as well. It said "success", but root checker still said there was no root.
Ironically root checker was taking a lot of time to figure out if I had root. Once I used the saferoot for Samsung and then looked at root checker, there was no 'thinking'. It was an almost instant confirmation that I had root.