I didn't want to include Paralysis originally, but it is worth lumping in since it is all related.
I mentioned the Slumber Sword in the Odin post.. and it got me thinking.
I tested the Slumber Sword while on level 99, and it works essentially all the time. When I remember using it at lower levels, it didn't consistantly work... and it got me thinking...
Ever wonder why Hold and Sleep doesn't work when you cast it on yourself? Ever wonder why the Sleep or Paralysis status don't quite work that well unless you have really high levels?
Onto the facts:
Sleep's effectiveness is based on level, like Odin is. The magic version has an additional hassle of being Wisdom based (it is very important for multitargeting the spell). The Slumber Sword does not need Wisdom to power it.
The exception here is that the GBA version has Slumber Sword's Sleep magic behave more like the Apparition/Change Rod (the status change works all the time, barring immunity).
Paralysis's effectiveness is also based on level. The magical versions (Pin, Hold) with the appropriate stat powering them can be boosted, but it is not as significant since it is single targeted.
Both status effects render a target temporarily useless.. but only level and Will/Spirit (for speeding up the timer) as far as I can tell are the way to combat this. Stop is significantly more effective anyways. Ever try to use the Slumber Sword against yourselves? It's pathetic. Ever try to inflict Sleep status with the Catclaw or Paralysis with a Whip on your own guys? It barely works. The D. Fossil (FF2US name) that attacks with paralysis barely paralyzes you. The only monster close to inflicting paralysis successfully is the King-Ryu (FF2US name).. and that goes away when you level up more.
So, there's your status analysis.
One other thing, Sleep doesn't always hit every target. That in itself made this worthy of being researched in the first place.