It's a bit perplexing. According to the time and altitude charts here
http://aireform.com/ntsb-fatal-accidents-a-page-with-further-inforecordslinks/fatal-aviation-accidents-2013q4/bonanza-n36ml-reported-lost-in-the-idaho-mountains-with-5-on-board-12113-12-noon/ The trouble started at 2:55 and terminated around 3:02. 7 min, averaging a speed of 180 mph and only losing 3000' He could travel 21 miles with altitude to spare. Could have possibly have made it back to McCall, but that's a mute point now.
He was an experienced IFR pilot. His instrumentation would have told him he was crossing just North of mid field at JC. Makes no sense why he would continue straight into no mans land. Judging by the pins posted by Pif-sonic it appears that he may have been initiating a turn to the South to perhaps setup an approach into the South end of JC increasing his decent rate to lose altitude. Unfortunately there are two ridges he would have to clear. The one close to his last tracked position, could have cleared, but at the last rate of decent reported. he would have Surly hit the one 2 miles to the South. For anyone going out that way it might be worth a look over.
I know everyone hates conjecture, but unfortunately that's all we got for now .For those of us on here who are capable of accessing the area and willing to put in a little time looking. It might help narrow down a search area a little, if we could somehow get inside the pilots head and ask ourselves, what would we do at that time, knowing we were crossing over a strip in a narrow valley 5000' below us, with shit visibility and no engine. Besides mercilessly shitting ourselves.