Thanks for posting.
It is possible to use a 10-second self-timer on the EOS 70D. To set the camera to use a 10-second self-timer:
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I don't recall this on my old T1i (not without installing Magic Lantern firmware -- note that's not supported by Canon, use at your own risk, and if you break your camera you get to keep both halves, etc. etc.)
HOWEVER... if you use the "wired" shutter release you can do this.
If you use a Canon RS-60E3 wired release which plugs into the side of the camera, you'll notice the shutter button on the remote release has a slide-and-lock which will hold the shutter button down continuously. It's normally used for 'bulb' mode shooting, but also can be used for 'continuous' burst as well.