> Can someone who's worked with APIs that accept updates give a code example of something that would be better if you accepted patches instead?
Concurrent edition of tabular data by several users.
User loads a HTML <form> with a bunch of widgets into her browser, edits some of the data and <submit>s. The usual implementation causes all data submitted via HTTP POST request, as simple KEY=VALUE dataset. Should two users send POSTs of same resource (same URI) concurrently, it is not clear what are real changes and what is unchanged, nor how to apply it to the resource.
What I'd like to do -- and indeed, some parts of my software does, albeit in non-standard way -- is submitting diff, in form of KEY=<original-value, new-value>. Makes it easier for the backend to serialize users' changes, and either apply them in atomic way or reject just the conflicting ones.