Ask HN: Can I expect enterprises to know what REST is?

I'm building an enterprise-y app to compete with some truly horrific enterprise solutions out there right now. Nothing too sexy. Invoicing and the like. I know it has a market because I use it along with many colleagues everyday at my day job and it really just doesn't work for certain types of employees. (I'm an engineer who is constantly on the road. I'm the type of employee it doesn't work for.) I've found a good solution for that problem. Furthermore it breaks pretty regularly and has caused some significant issues. My company would probably switch but they're using one of the major players. The self-proclaimed "industry leader" so using the other guys would probably be even worse.

My question is about integration with whatever they may want to integrate with. For example, my company currently uses software that is built on top of MS sharepoint. The company that makes it actually comes to your building and installs it on a server on your floor somewhere. I want to create a saas alternative that would be web based (and not using sharepoint). Can I expect the typical IT department to be able to make sharepoint send a GET request and programmatically do something with the response? I can't imagine a single reason why they would ever need to POST anything but retrieving financial data to use in their other accounting software may be necessary. Would they be happy with the ability to download a csv?

I'd love to hear anyone's thoughts especially if someone has experience dealing with something like this. Thanks!