I should add that the risk with using Brett Terpestra’s API via heckyesmarkdown.com/ relies upon Brett kindly making available and maintaining this API. But in the unlikely situation that he stops supporting this service the DEVONthink Web Clipper will become broken too.
It’s great to hear that conversion to/from Markdown will appear within the Data > Convert menu at some point. I fully understand the issues regarding standards and the complexities that this adds but considering Brett is in the process of commercialising his nvALT application, I think there’s very little risk in him abandoning his conversion API as it’s a central aspect of the nvALT product offering.