厳しいそうなので / 厳しそうなので

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Aug 12, 2011 18:38 Japanese_language 「そう」
I came across an interesting example.

a. 彼は厳しいそうなので
b. 彼は厳しそうなので
The only difference is “い”, but both have quite different meanings.

a. I (have) heard that he was/is stern,
b. It seems that he is stern, (or I guess that he is stern,)
(The difference of the tense does not matter.)

Do those who learn Japanese as foreign language learn this? I do not remember studying this in my school days. However, the difference is clear, and both usages are common.