Thanks for the details, That is TTL is like a Canon strobe and has to be on camera or with a TTL connector out of camera.
The feature I can get with my 100D , SL1 is that I can use a radio transmitter on top of the camera to fire my Broncolor Studio Strobes in Live view.
More of a manual control.
On the T4i, I developed a Skill to the cost of wearing the camera a lot, is compose in live view, when ready go to OVF shoot one or several shots,
with the camera blind and then come back to live view to re compose, and then repeat the operation. Once you get the hang of it seems like if you will have this function in camera.
As I said the SL1 has this feature natively.