I really like watching Dub-only viewers' reactions, seeing as to how most of us jp viewers tend to get spoiled through episode titles and summaries
Honestly, it's probably even harder to remain spoiler-free as a dub viewer, given the fact that episodes come out in Japan several months ahead of time, and people (at least on the internet) seem to think if you don't watch it when it comes out in Japan, then too bad for you. Even if it's something that tries not to spoil people, sometimes it's just inevitable. Like it's so hard to visit Serebii.net and not get anime spoilers, even though Serebii attempts to hide them. What annoys me most is when Serebii makes a post saying "We've updated Ash's biography with the new Pokémon he captured in this week's episode." While that's not a spoiler in of itself, if the "Next in Japan" section has been showing a picture of a Meltan for the past week, then it's almost assured that new Pokémon he caught was a Meltan, which I would classify as a major spoiler. You could argue that if I don't want the spoiler, than I shouldn't be on Serebii.net, but then I would miss the news. (Really wish Serebii was better about that...)
Even off the internet it can be a problem. I was spoiled about Ash winning the Alola League by a jerk ex-friend of mine who just casually brought it up, even though he knows I only watch the dub. His excuse was that he assumed everyone knew already. I was so angry at him. (For the record, it is not because of this spoiler that he's no longer my friend, we had a falling out a few weeks later, though I'm sure this event contributed.)
I would think it's much easier to avoid episode titles and summaries than just the casual ignorance people often have towards dub viewers.
Sorry, didn't mean to rant, just kind of came out that way...