I came across this string stretcher device. It claims to properly and evenly stretch new strings and maintain tuning. 

I never really made a point to properly stretch newly strung strings. Can anyone comment on the practice of stretching strings and or the relevance of such a device?

Apparently:
"A lot of musicians mistake their guitar tuning problems as a guitar problem. More often than not, the guitar is not the problem. Tuning problems are likely the result of strings that have not been stretched properly."

[The Stretcha](http://www.guitarscanada.com/content/517-string-stretcha.html)