WPF Automation – test injection approach to application testing

One QA in a project, one and a half thousand test-cases for C# WPF financial application, three weeks to pass complete regression testing at once management wants to make release cycle shorter. Tell you what test-framework has been written in Deutsche Bank to automate testing of WPF UI including lots of custom controls and how we use it to make integration tests and QA life easier. Also tell you why test injection approach had chosen.