In this mini-episode, Kain our host, discusses the tricky problem with Tau faster then light travel. With an empire in a stellar cloud about 300 lights years in diameter and the vastness of the Damocles Gulf to the corward side of their Commonwealth, they need faster then light travel to have a realistic chance of existing in 40k.

In the beginning there was the Gravitic "Ether" Drive in which the Tau would 'skip' across the warp. This allowed them a 1/3 speed of an optimal operating Imperial drive (without the perils of the warp aspect and entirely reliable, unlike human's own warp engine). 

Then there was a retcon where they were given close-to-lightspeed capabilities.

Finally, they're opening wormholes to new parts of the Galaxy.

We'll do our best to straighten it out for you. Enjoy!