Blocking means a way to shaping a panel, also shrinking or stretching a panel, sometime a combination of both can be done with blocking to a desired shape. Then the panel gets smoothed off on a forming dolly prior to wheeling and finishing it off
I think that in England they call this ''hollowing'' ( not sure ?)
Peter
PS in the US most of shaping is done with heavy hammers like the Yoder and other machines . also the panel is finished off in the same way