Seriously, three problems arising from this incident
1. The non-use of the bays at Blackfriars to turn trains from the South this morning (even after power had been resored)
Bay platform 4 is under possession except for a couple of hours each night; this was given up as soon as practical - by about 0830. Besides, the northbound through line was open and live except for a 30 minute period. And in any event the bays were used.
The main issue was drivers being in the wrong place. I gather that a few extra were called in.
Aside from the trapped train, almost all trains were got to a platform relatively quickly, and only moved forward when it was reasonably sure there would be another platform for them to go to. And use of the bi-di kept things moving.