Hi Jim,
The "report" that you reference is an extract taken from the Cruck Catalogue published some time ago by the CBA edited by Nat Alcock. Unfortunately this book is now out of print but I do have a complete version of the whole book (184 pages) in pdf format (3mb) if this would be of any use to you ?
Nat is currently working with us in Steventon, Olde Berkshire where we are examining 2 seriously old cruck buildings. Dendro on the first cruck has failed to yield a date but since this is part of building complex where the main range dated to 1358 we will now try radio carbon dating to see whether the cruck is older or younger than the main range. A few houses along the road we have a similar situation where the main range has dated to 1299. Now that's a real gobsmacker to see first hand.
The reality is that we don't really know the full extent of vernacular buildings that still exist in our towns and villages, nor do we know what we lost before listing began.
Regards
Ken Hume