I think with OD you just have to assume people are dating other people at the same time, but I think it's one of those things you don't discuss, like what they're doing if they take a long toilet break. I've had one person tell me that their weekend plan involved another date and I found it a bit odd, I think it's fine to say "having a drink" and I wouldn't even mind if they claimed it was with a friend.
As I see it, we're all on these sites for a reason, we're all trying to get our money's worth, either literally or not, you just can't pretend that it's as natural and serendipitous as locking eyes with someone across a crowded supermarket aisle etc.
I think OD relationships would have a much greater chance of success if people did keep their mits off the sweet trolley. Maybe I'm a hopeless romantic but I like to think if there was mutually, actually something real there people would be able to do that. But I think the nature of meeting so many people is that you're going to meet lots of people who you're sort of into, and because it's a format that prompts action, people are maybe inclined to arrange second, third and fourth dates just to see what happens; when normally in RL they'd let it slide. I'm not doing OD down in that respect, I think that structure is great, but by god it has its downsides.
I still think SpaceMan is a twunt though. Not for dating other women but for cancelling twice. If it was me I wouldn't give it to him, unless he started actively lying. I'd just let it slide, no contact, next.
It sucks though, I had one cancellation for a second date and it's hard not to take it too personally. But by the same token I'd been a bit blase about it as well so I think we were mutual backburners who decided to turn off the gas.
Apologies for the essay. For what it's worth I love lurking on this thread as I think unless you are ODing you have no idea what a odd world it is.