[url]http://starwars.wikia.com/wiki/Double-bladed_lightsaber/Legends[/url]

You're not just welding two lightsabers together. It wasn't that nobody thought of it, it was more like nobody could get it to work until that time. It was created in 4,000 BBY, which is still relatively early in the Star Wars timeline all things considered.

Honestly tho, why would I lie?