| Dormant growth buds on rhododendrons occur at leaf axils (where leaf joins stem) - buds are not found under the bark into between rosettes of foliage (or at points where there once was foliage). Azaleas have dormant buds all along the stems just under the bark and will sprout from just below a cut no matter where you make it. As for the hedgehog, I vote no. While technically you could, unless you happen to have a formal azalea hedge, selective pruning with hand pruners is going to lead to a more natural shape and long term - a healthier plant. Because shearing is non-selective heading, you will stimulate bushy regrowth creating a twiggy dense outer shell. No light reaches the plant interior and eventually you'll have interior of leafless dead wood. Some years back I tried the gumdrop shaped shearing of azaleas and luckily recovered from the phase :) What I did end up doing to help the two unfortunate azaleas that were victims of my shearing....a complete renovative pruning where I took them down to about 6" of bare stems to let them grow out again to their natural shape. | 
