I you work with a lot of files and try to get an overview over an application flow, splits are very helpful, as you don’t lose the focus on which files you opened. But after you opened some files, the editing region gets very small. Now is the moment to open up the file in an tab. If you just use :tabe an empty tab is opened. But if you use :tabe % the currently open file gets opened in a new tab.

Using e.g. the lint-modus of php you can check the syntax of the current file using ‘:!php -l %’.