Nice thought, Dunc.
IMO, the "ABOK", is worth the 50 quid, for the drawing and artwork, alone.
Even the dustcover is a work of art.
There,s always something new to be found within it.
I would think I,ve spent a good few hundred hours immersed in it
If nothing else, you,ll find it great for propping open the window, come the next warm spell, or as a temporary step for re-emulsioning the ceiling.
Happy knot tying.
Ceeg