The best validation and source of improvement for wireframes is to test them with real users. In the next chapter, we will create test designs and run the tests with real users. More often than not, we can't run as many user tests as we would wish. Testing with real users takes many resources, time, and money. If we are limited in any or all of those resources, we could skip testing our wireflows, or at least the first iteration of them, and run a Wireflow Improvement Workshop (WIW) instead. If you can do a lab or remote user test, that can serve as a base for a WIW. You only have to gain from running such event.
The WIW is a collaborative meeting session, during which we focus on the current iteration of the wireflow, with the intent of considerably improving it. This is also communication exercise, where many ideas of improvement can be shared, discussed, and evaluated.