Why is 五右衛門 read "goemon"?


Why is the name 五右衛門 read as ごえもん?  
How can the three kanji 五右衛 be read with only two syllables?




Originally, these kanji were thought to be pronounced as:

> 右衛門: _u we mon_

But since Japanese _u_ and consonant _w_ have little difference, the actual
pronunciation was like:

> 右衛門: _wwe~we mon_

Later, undergone the phonological change that merged _wi, we, wo_ into _i, e,
o_ :

> 右衛門: _e mon_

So the truth is 右 and 衛 share a single syllable, but the fact has been
obscured by the sound change.




[Some](http://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q143434759)
[people](http://twitter.com/#!/_ryu9/status/11886981072) say that _goemon_
(五右衛門) and _iemon_ (伊右衛門) are pronounced like that since it's hard to
pronounce 2 or 3 continuous vowel sounds, as are supposed to be read as _g
**oue** mon_ (ごうゑもん) / **_iue** mon_ (いうゑもん) per syllable.

