I just saw a beautiful play on Jinteki.net combining False Echo and DDoS : but the question remains, would the combo make it so that multiple False Echos can be used in one single run with DDoS? Would each ICE be counted as the outermost ICE when the previous one was bounced with False Echo during that same run?
It was a beautiful combo with two Hyperdrivers and a Keyhole in conjunction with the previously mentioned combo: the runner had 10 clicks in just one turn to run with Keyhole multiple times for free on an RnD that had no rezzed ICE, hence, False Echo could bounce the ICE in a single run and continue to hammer RnD with Keyhole.
If the DDos & multiple False Echos combo does't work in a single run, it is still great if you have all those Hyperdriver clicks and just bounce one ICE at a time and afterwards hammer RnD with Keyhole.