v0.1
Spell Scroll
Scroll, varies
A spell scroll bears the magical words of a single spell,
written in a mystical cipher. Using an action to read the
scroll allows you to cast the spell without components.
If the spell written on the scroll appears on your
class’s spell list, and the spell’s level is one that you
can normally cast, you cast the spell successfully.
Otherwise, you must make an Intelligence (Arcana)
check to see if you can successfully cast it. The DC
equals 10 plus the spell’s level. On a failed check,
reading the scroll only consumes its magic with no
other effect.
v0.2
Spell Scroll
Scroll, varies
A spell scroll bears the words of a single spell, written in
a mystical cipher. If the spell is on your class’s spell list,
you can use an action to read the scroll and cast its spell
without having to provide any of the spell’s components.
Otherwise, the scroll is unintelligible.
If the spell is on your class’s spell list but of a higher
level than you can normally cast, you must make an
ability check using your spellcasting ability to determine
whether you cast it successfully. The DC equals 10 + the
spell’s level. On a failed check, the spell disappears from
the scroll with no other effect.
That is a much narrower scope clarification for casting spells from scrolls. In v0.1, "Otherwise" could apply to any portion of the if((boolean) spellInClassList() && spellLevel <= castingLevel) clause, allowing anyone to use a scroll.
The newer wording makes the limitations quite clear now and closes that loop hole.