[Bubbles]

I think you could make the argument that IB had about 4 different incarnations, and TR is on it's second.

Original IB (Sol A)
Second IB (After pilfering all of Trans's melee/wizards)
Third IB (probably golden age)
Final IB (Blackwater/Doze era)

Then original TR (Darkwind + Pantheon merger)
Current TR.

Still less work than drawing up the FB/DA/TMO history.

They've always been a presence.