The last hiragana form is stated as an "alternate" form. Now my question is, can it be used today, or is it something that is out of practice and just around to preserve the history of the origin of hiragana? Unlike the "alternate" forms of き and さ (which is strictly for computer font and not meant to be used for writing), the alternate form of そ is not in the same category. So my question is, when and why did that alternate form change to the more common form that we have today? Is there any interesting history behind it? And why isn't it taught anymore?