Pros and cons with aluminum covering wet holds

The picture with aluminum covering wet holds is from a video. It seems this technique is quite known in limestone areas as it makes it possible to climb on partly wet routes. The aluminum mustn't be placed on any sandstone which can break when wet. When it comes to limestone, be careful and only cover solid rock. It is also important to take it out after you have climbed as it does not look nice and furthermore, the aluminum makes the rock dry slower. Littering is of course also a problem that must be avoided. In general, try to stay away from the technique but sure, being on a road trip it is a great way to have the possibility to finish your project.