Microsoft have done a great job of presenting the D365FO xml files just like other .Net language files in Visual Studio, but it seems like the TFS merge tool is the same one that's been there forever and it has no appreciation of the xml file format of the D365 files during check-in/merge. If automerge is enabled, this can result in corrupt files at check-in, I've seen this with labels, form file extention classes and table file extension classes and the merge experience is actually a backward step from previous AX versions. I would like to propose that MS develop an intelligent merge tool that understands the xml files that make up a D365FO solution and provide intelligent "object based" merging, so for instance, if developer A and developer B both check out the same form as a multi-user checkout, Developer AQ adds a control to a particular group in a form and developer B adds another control to the same group, regardless of who cheks in their work first, the tool would understand there are 2 different controls added to the form and provide a merged result that contains both controls.