Looks fine to me, of course real proof only seen post use. Afaik, Puro has used assembly string on the larger/largest filters manufactured for a very long time. As the Rotella filters seem primarily for diesel application many/most would qualify in that category. Other than purely aesthetic considerations, never seen post use where it caused any functional issue. I find it assuming though as it does seem to put off some folks.
Thanks for c&p.