I had the same delema with my last brisket. I foiled it for the last few hours and it came out nice and tender. Like you I crave the crusty bark but the foiling also tenderized it as well. It really wasn't bark any more. I did what FatDaddy suggested and threw it back in for another hour. That seems to be the trick.
It was a brave man who first ate an oyster.
Brinkman Stillwater Limited, Great Outdoors Vertical charcoal.