Yes, a minimal amount of water will escape but I haven't found it to negatively impact my brew. One of the best things about the aeropress is the experimentation and variety, so I encourage you to try this and see if it makes a difference. James Hoffmann has a video on this technique (jump to 2:00 to see the start of the recipe): https://www.youtube.com/watch?v=j6VlT_jUVPc