I doubt anyone _actually_ learns Mandarin without learning how the common characters are pronounced... Unless you don't have to verbally communicate with a teacher / fellow classmates?
When I go through a text I understand I either don't sound the words or pronounce broken translation in my mind.
I've doubted this approach a few times because, as you say, it's uncommon, but I'm sticking with it and I'm curious what comes out of it in a year or two.
For instance, rewriting your sentence above into something somewhat like this:
I finish wonder this; accept word element character language, you not think word ability read language.
Hardly readable once you start getting long sentences in books. Japanese speakers can't just natively go ahead read and understand 95% of a Mandarin book even if they know all the Simplified/Traditional Chinese characters which are not commonly used in Japanese. They can sometimes understand simple sentences, and can more easily understand, say, street signs.
And I can't communicate verbally at all...
That said, the voice in my head just pronounces the Japanese Kanji in my native Cantonese...