On second thought the algorithm may have accurately measured my potential fluency. When it topped off at 65% that was ridiculous. I couldn't understand a word on the street or pronounce two words correct in row. To say I understood nearly two thirds of Spanish written or spoken at the time is far more than I understood. Even now, I really don't understand 50% of what is going on and there is no slow button in real life.
I think of it more like a motivator. It's my Duolingo fluency and it does have value. If you don't practice, you will lose fluency rating. It may be artificial, but for me, I have put a lot of effort to reach this stage and I don't want to slowly fall back after forced practice in school (MANY years ago) or with my Spanish learning CDs.