The core alone has the strength needed, so when I did the splices on my boat, I did not worry about getting the core all the way to the splice. This was especially a concern with the fittings I chose, as the eyes had to be larger than needed to get the pieces through the locking splices. I haven't had a problem with this, and the service sounds like a good idea.
The splice I chose was this one:
http://l-36.com/brummel2.php