Confused About Cleaned Coins

I have a story to share here on this subject. One of the coins from my late uncle's collection was this 1766 Pitt Token. For those who don't know about these, they were minted in England. On the obverse is William Pitt, the elder, who was Prime Minister at the time, who led the movement to abolish the Stamp Act.
Sometime in the late 90's, my uncle sent this coin to PCGS to be graded and slabbed. It was returned in a plastic flip, ungraded due to "environmental damage".
OK, it was a more than 200 year old copper coin which was filthy dirty, hard to see the details, but surely it has historical significance?
He left it that way and I eventually came to possession of it.
I brought it to a local coin dealer to get his opinion. He noticed it was rejected by PCGS, refused to even examine it, and told me it was worthless!
Figuring I had nothing to lose, it got a bath in Franklin Mint coin cleaner.
Much of the filth was removed and the details are more pronounced.
I haven't brought it anywhere to be re-appraised for fear of being told that I have now completely destroyed any value it apparently didn't have!
This whole clean or not clean thing is perplexing . .

Coins that have been cleaned, I will dock 50% from their value.

I understand this, up to a point. An improperly or harshly cleaned coin should suffer depreciation. But what bothers me is that a grading service can charge you for a dip, call it "restoration" , then grade and slab it and everything is honky dory. But if you do it and submit the coin, you get cleaned with details and no rating.

I understand in the European coin market, they deal mostly with raw coins and don't buy into the certification thing like we have here . . just sayin'

Actually, if you dip a coin and dip it wrong(as most people do), you get the dreaded improperly cleaned notation.

If you dip a prime candidate coin correctly(neutralize the acidic dip, throughly rinse with distilled water), you will almost certainly receive a straight grade as it would if the coin had been professionally conserved.

Most coins are not good candidates for dipping and dipping must be done in a very precise way, you are paying for that "professional" expertise when it is done by a conservation service. Any old fool can dunk a coin into a jar of sulfuric acid and thiourea but you really have to know what you are doing to dip a coin correctly

As a general rule at coin shows I look for cleaned coins that have been greatly reduced in price. If not harshly cleaned, makes little difference to me as long as it looks OK to me. You all should remember that the one big thing about a cleaned coin is the value. By this I mean if you plan on selling coins, cleaning makes a difference. If you are like me and never sell or plan on selling a coin, who cares. What difference does it make if it is going to be in my collection until my end. And at that time, I really don't care. As long as a coin looks OK to me, it is none of anyone's business if cleaned or not. My coins are my coins.