It's a really difficult situation clearly. I'm pretty sure I heard a former fire brigade safety officer saying that the main problem in the communal areas isn't so much the fire as toxic smoke and sprinkler systems won't help with that. The link below would seem to confirm the problem. In this case toxic smoke/fumes and fire was entering the flats via the exterior of the building so again sprinklers wouldn't have been totally effective. How feasible would it be to retrofit sprinklers inside all the blocks I wonder? It does seem like a sprinkler system inside the flat in which the fire started could well have prevented this tragedy but even so there'd still be the potential for external fire sources to set the cladding ablaze.
http://www.bbc.co.uk/news/uk-40297466
The guy in question here seems to be pretty fit looking and he made it from the 14th floor to the 4th before collapsing. Luckily a firefighter got him out but older, more vulnerable people would never have made it.
Respect to anyone who's prepared to go into that sort of environment, however well trained they are!!