RUMOR: Devs using underclocked kits explains lack of actual Wii U game footage at E3?

From a report conducted by Hit Detection:

Developers have underclocked development kits, and worked hard to deliver titles running on that hardware to demonstrate live at E3. However, due to titles not looking much better than what is currently available on Xbox 360 and the PS3, Nintendo decided late in the game to not show those titles and focus instead on tech demos.

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