The author states that he intends to be fluent by 2016 by studying in his free time. I don't think this is likely to achieve fluency unless you're living full time in a Chinese speaking enviornment. Of course 'fluent' word that tends to get thrown around indiscriminantly and rarely used in the linguistic sense of true fluency. If he means functional or conversant, then it's definitely doable. If, however he means C2 on the CEFR scale, then 5 years of full time study might be enough to achieve that, but it's not guaranteed.
I will say that he's on the right path using Pleco & spaced repetition. These tools mostly appeal to us engineering types, but I can tell you that they truly exploit the power of your memory.
Chinese is just a harder language than others. It presents numerous challenges for non-native speakers, especially westerners. These include:
* Difficult writing system
* awkward pronunciation
* difficulty distinguishing tones
* numerous characters associated with any given syllable which makes it diffulcult to infer meaning of new words that you haven't heard before.
* abbreviated forms, (i.e. huan2bao3 - huan2jing4 bao3hu4)
* Larger vocabulary. To understand 90% of all content in English, you need to know about 5000 terms, with Chinese, that number is about 9000.
So, if you're the type that likes a challenge, then it can be very rewarding, but just realize what you're really up against. Most folks who take it on give up before reaching true fluency.