Posting for the new guys in case they read this stuff and start entertaining the possibility of perma cycling.
Pros absolutely do cycle down between shows. They also have a medical team frequently monitoring their bloodwork and adjusting things on the fly, plus they take a ton of supplements each day to ensure their health doesn't decline too much.
The pros also understand the damage they're doing to their bodies and accept their longevity is likely shortened. Keep in mind though - the boys at the top are genetically gifted, as in they are the .01% of the population who have the genetics to make it that far in the sport. The rest of the population (pretty much all of us) are genetically generic guys and will never be able to compete at that level with those dosages of compounds. Try not to compare yourself to the guys at the top. Rather, compare yourself to who you used to be and focus on becoming the best version of you that you can be.
You'll definitely need to cycle off. If you're not concerned about your natural production/don't care about having kids, then do blast/cruise the proper way. Cycle off, drop to a true TRT dose, give your body the time/supplements it needs to heal for awhile, then get back on cycle once your blood work shows the damage is repaired. While on cycle, you should be supplementing daily with organ supports as well as whatever else your blood work says you need.
One of the most important tools of PED use is frequent blood work. Get it done while natty, then again and again while cycling. The frequent blood work will give you snapshots of your body's health that will paint a bit of a picture for you so you can adjust the conditions. The ultimate goal is maintaining your health while you're improving your physique.
Despite the lack of side effects, the compounds are stressing your body and organs. There's no human on Earth that has a unique physiology in which PED use does not stress/damage your interior health. Your liver will take a beating as it only has so much ammo to fight with, your kidneys will take a beating from the increased blood pressure, your heart will grow thicker making blood flow more difficult, and these are the just the tip of the iceberg of what your body is dealing with on the inside.
There's no point in growing as a man if you're unknowingly shaving decades off of your lifespan.