Man you guys are at high levels when you take that thing on..... I party is usually lvl 40 or below and I have no trouble taking out the wall with Titan and Beserked attackers (this is on my SNES). My usual level for finnishing the game is 50 (just tp get nuke).
Don't forget that if you're uber leveled to use the spell (White or holy) with Rosa, its a major damage producer.
I only found out Rydia could get Meteo after I decided to take a group to level 99.
On a side note: The sealed cave is an important experience area to complete if you're not into leveling throghout the game (like me). So I suggest that any low level parties not skip the entire sequence by using that warp trick. If I did, it would take me forever, doing nothing but leveling, to get "float" for a certain couple side quests.