The Romanization of Chinese

The Language Log has recently written a post regarding Chinese (Mandarin) language and pinyin, the system of romanization meant to standardize the language's pronunciation. 

A few days ago, Cyndy Ning sent me this Website for learning pinyin pronunciation.  It has both female and male voices which you can activate by clicking on nánshēng 男声 and nüsheng 女声 just above the initials D, E, and F at the top of the table.  I also found similar tables here and here.
This is a neat tool, BUT, in playing around with it, I discovered that nearly all of the 4th tone -ANG syllables in the system come out sounding like -AN.  A similar phenomenon holds true for all other 4th tone syllables ending in -NG; that includes -ENG, -IANG, -ING, -IONG, and -ONG, -UANG.  This is especially the case with the male voice, where I have to strain very hard to hear even a semblance of a [ŋ] at the end, and sometimes I can't hear it at all.  Mind you, this is only on the 4th tone!  I can hear the final [ŋ] well enough on all of the other tones spoken by the male voice, and I can even hear it fairly well for 4th tone syllables when listening to the female voice.

One could respond in different ways to this.  Of course, as the author describes, female voices are generally higher in pitch than male voices.  The ending could simply be less audible in the male reader's voice.  Or, as the author surmises, there could be a physiological cum phonological transformation that manifests itself in a 'defective' way as described above.

However, when I read this I had a different reaction.  During my experience as an elementary Chinese language tutor at the undergraduate level (my Chinese friends get a kick out of this), often have I held the hands of native English speakers as they take their first steps into the world of Chinese pronunciation.  Most often, the first thing I told them about Chinese was that pinyin is a misleading system of romanization.  This tool, intended to simplify and standardize Chinese pronunciation, has been a source of endless confusion for my students. 

For example:
chu (out/exit) 
This is pronounced "choo" in English equivalent.
qu (v. to go)  
Looking at this word, one would assume that the consonant is pronounced differently than chu, while the vowel is pronounced the same.  Wrong.  The consonant is the same, and the vowel is different.  Based on the above explanation for chu, this should be pronounced "chü."

Also:
ju (mandarin orange)
nü (female)
In both of these, the vowel is pronounced the same (ü), yet they are written differently. 

Similarly confusing:
xiang (fragrant)
This is pronounced "shee-ahng."  (The a sounds like the a in "all")
xian (fresh)
Here the pronunciation of a changes.  It is pronounced "shee-en." (a makes an e sound, as in "echo")

Given this logic, the author of the post is technically incorrect in saying that the 4rth tone words ending in -ang sounds like -an.  This may be true if read in English, but it is not by the irregular rules of pinyin.  (The ending which should be [ŋ]  sounds like [n].)  Of course, this is not intended as a critique of the Language Log (for which I have nothing but the highest respect), but rather a cautionary tale and sympathetic critique of pinyin for current and future language students. 

Of course, I also agree with those who say that it doesn't matter.  In the context of a conversation, it is usually easily to discern that the speaker intends to pronounce -ng instead of -n, just like native English speakers would not be confused if one said "runnin" instead of "running."  Still, I wouldn't use it as teaching material.