Thank you for starting this thread, John.
I have always understood that it is a given that SY are working on old material and leads that in all probability have gone cold. The chances of coming up with something new after all these years is there, but it is small.
Icabod and I were discussing the matter last night and I still stand by my thoughts then, namely as summarised below (quoted post):
But icabod, hasn't this always been one of the shadows hanging over the investigation of Scotland Yard, namely
the fact that much of their work is predicated on old material, which may or may not be completely accurate and may not have been followed though to completion at the time?
Surely it has been a distinct possibility from the get -go that the SY investigation might never bear fruit, if none of the old leads go anywhere, and new ones are not generated?
The base information SY have to work with is only as good as the PJ left it. And if there were things that the PJ didn't follow up, resulting in possible leads gone cold, there's not much that can be done about that now.
I'm not saying that the PJ did not in general follow up leads properly, or that SY can use the fact that their work is heavily reliant on that of the PJ as an excuse for not getting anywhere.
But the fact remains that if there happened to be any leads not properly pursued by the PJ, for whatever reason, this could have forever stymied progress in the case.
We knew this when we (the British taxpayer) signed what has become a blank cheque - and we signed it anyway.