I have Elton John running through my head at the moment, since typing those three words. Sorry if I’ve earwormed anyone else.
There are two verbs that many people have trouble conjugating and using correctly. (Okay, there are many, many more than two. But I’m talking about only two today.) There’s shine the transitive verb, which conjugates shine/shined/shined, and there’s shine the intransitive verb, which conjugates shine/shone/shone.
I see heads shaking already because I used grammatical terminology. Transitive verbs “transfer” action from the actor to an object. “He shined his shoes.” He performed the act of shining(here meaning “polishing”) on the recipient of the action, the object: the shoes. (I’m partial to Kiwi brand polishes, personally.) “He shined the flashlight into the dark hallway.’ He performed the act of shining, which in this case means aiming the lit flashlight, on the recipient of the action, which is the flashlight itself (the thing being aimed). He shined it into that dark hallway with the creepy cobwebs and peeling paint.
Intransitive verbs don’t transfer any action from actor to recipient (object). “The sun shone a dusky orange through the clouds of dust.” The sun’s doing its sun thing; it’s shining. Light’s coming from it. “Her face shone with delight.” No action’s being transferred. This is a figure of speech; her face is not emitting light, like a star, after all. Not literally.
In Garner’s Modern American Usage (3rd edition), the error of using “shined” for “shone” is given a Stage 2 on the language-change index. That means it’s unacceptable in standard usage. It’s seen enough that people might wonder whether it’s an error.
It’s an error.