Q.Your Page On Pruning Suggests Cutting Down To 1 To 3 Inches. How Long Will It Take To Recover From That Radical Pruning?1!
My burning bush is about 6 years old and is 4-1/2 feet tall as this year had the most Beautiful RED leaves ever and they held on for a very long time. If I prune down to 3 to 6 inches will it take another several years To give me that kind of showing? Thank you, Ron Smith connemara.rs@gmail.com

Certified GKH Gardening Expert
That type of pruning is reserved for diseased, or aged shrubs that will not perform well anymore! If you are seeing the growth that you want to see, then I would NOT prune it hard. A light pruning will be much better, as it would take a couple of years to fill out again.
https://www.gardeningknowhow.com/ornamental/shrubs/burning-bush