Kenne, sounds like your approach should work. The pistons collect crud and require polishing and lubing with Brembo red grease. It depends on your riding conditions and habits cleaning the bike. Sometimes just exercising the pistons, like Turbo has stated, works. In my case, the rear caliper had just one of the pistons barely working and keeping the pads engaged, cooking the rear rotor. Once I discovered and fixed that, I went ahead and serviced the fronts. Trouble starts when the rider trusts the shop and during brake service they just change the pads, bleed the brakes and send you off. At the time of pad replacement a careful inspection and off-the-bike cleaning of the caliper should always be done. Grater trouble arises when the seals are reinserted in the incorrect position allowing fluid to escape and contaminate the pad leading to catastrophic brake failure. This is why Brembo no longer sells seal kits. Kenne, to that effect your method avoids that fatal error. Some vouch for deglazing the rotors, which I have never done. Squealing was cured with special purpose, high heat grease applied to the back of the pads.
Your Rocket should stop with a single finger squeeze. If it don't, have your calipers carefully inspected by a serious reputable mechanic or yourself. Get a torque wrench, a set of metric sockets, a way to lift the front of the bike and have some fun servicing your bike.
Good subject to converse about. It might save a fellow rider's life.