I dont ge the connection with failure point (DIR driven) on the reducer/adapter o ring.
the "preferred " way to cure this is to use a 1/2" plug, and abandon this port, and use one of the other 3/8" ports in its place. That said, the block off plug has an o ring as well as the adapter! effectively killing the "O ring failure" reasoning. Also, the reason for NOT using the 1/2" port for any hose,(DIR) is to create a redundancy in parts. = same hoses, same fittings, all 3/8" , KISS , keep it simple stupid. I use the adapter, and have not had a problem of any kind. And if that sealed o ring ever gets "extruded", then I most likely have bigger problems dont I ? In short, im not loosin any sleep over the extremely simple and sturdy adapter.