If the dropout to head tube distance has not changed, less offset means more trail and more stable steering. 4 mm should be noticeable but not a major change. If the fork blade length has changed, now you've raised or lowered the front of the bike, changing the head tube angle, adding another dimension into the mix (and slightly altering bike fit).

Edit: I haven't addressed your inquiry on my fork failure because I really don't want to revisit it again. I hit numbers one and three on merln's list hard. (Well the collarbone was just a collarbone.)