charlieb skreiv:
Anyone have a theory about why "pith in" turnings are more proned to
cracking than "pith out" turnings?

charlie b
[snip]

If you haven't already you should read this book:

URL:http://www.amazon.com/Understanding-Wood-Craftsmans-Guide-Technology/dp/1561583588/ref=pd_bbs_sr_1?ie=UTF8&s=books&qid=1204792325&sr= 8-1