First I checked Google, but ... "teir-dal.tripod.com was first indexed by Google more than 10 years ago" was all it offered. Similarly the Wayback Machine, which would normally be perfect for this, didn't start archiving the site until 2011:
https://web.archive.org/web/20110501...dal.tripod.com. No help there ... and of course the sneak pulling page itself has no dates on it, even
in the source code.
But, the page does have a link to clear out-of-era content:
this page for the Rogue epic "1.0" (2005). If I were Nilbog, my default assumption would be that the sneak pulling page is similarly out-of-era.
AFAIK there's no way to date that specific page, but maybe someone else will have a better idea.