The basic spells aren't worth it in any way, simply because you need to invest like 10x the fragments you get from disenchanting just 1 spell. (assuming Lv2 MA)
Even if you've got a fully maxed out Lv5 MA, you still only make what, like 90'ish fragments from disenchanting 1 PoP/EE spell?
So you'd need to disenchant 4 spells to make just one back, and get only 1 vision vapor in the process?
That's pretty insulting to the intelligence of most players who can do even basic grade 2 math.
At least if it was a pack of 3 spells & say 5 VV's, it would be more usable, though still come in at a slight loss in fragments for even a Lv5 MA.
Remember: the biggest limiting factor for most players will be how to keep a steady supply of spell fragments coming in.
Spending potentially up to 10x what a single item would give back is well, many, many words I'm not allowed to say without getting perma-banned!