User blog comment:Legionwrex/How did Saren reach the Citadel?/@comment-1440333-20130507094740/@comment-1440333-20130507183504

I dunno - In the first game most of these little plot holes were covered, ergo we could imagine that the Conduit works in a different way...

After all a more important question would be how a ground tank comes from a Mass relay on a planet, that probably isn't facing directly at the Citadel, travels completely across the galaxy without hitting ANYTHING (seriously the odds on that?), passes through a dangerous nebula with no damage, and a devastating space battle with no notice, and then manages to somehow pass through the Outer layers of the Citadel without causing damage to the structure itself, only to arrive unscathed at the Relay monument.

There's your plot hole!