Its not uncommon for members of a once close group or good guild to try and reform. This comes from the natural instinct of.. "I remember playing with so and so and doing such and such. Yeah, that was fun." and "Reliving the good old days" sorta.
Ive heard of several guilds doing this, including one on my current server and that guild after reforming is one of the better guild on my server.
Alot of times it gives many players a fresh attitude about the game and sense of belonging when welcomed back into the original group, allowing them to play harder and help more knowing that they were valued enough to come back and help reform it.