Can you depend on Twitter?

One of the reasons I love RSS (and other) feeds is that they effortlessly alert me when someone I follow posts something. So it was this morning, when James Morley published Collecting and displaying contextual tweets for cultural heritage records. I've known James a long time, and admired his approach to gathering and visualising data, and this was his first post in almost two years.

It's about automatically harvesting Tweets using a tool called TAGS – Twitter Archiving Google Sheet, and he shows in detail how useful it can be. I might even find a use for it myself. But here's the thing. James recognises some "potential issues," among them this:

We should also remember that tweets, or indeed whole accounts, can be deleted (for a multitude of reasons) and accounts can be made private and thereby hidden, at which point there will be technical issues around trying to display something that no longer exists, or if you archive the full tweet text then both legal and moral questions arise about keeping a copy.

That is all correct, if you don't want to break Twitter's terms. If you're adding valuable information to a website, should that be your primary worry? I know there are people who save tweets, their own and others', to the Internet Archive, and I assume that may be breaking the terms too. But it strikes me that if, like James Morley, you are curating some information to make it more accessible, more interesting and more valuable, then you have some sort of right to ensure that it doesn't just vanish.

How exactly to do that is beyond me.