Leno kind of threw a unexpected twist into the fisher thing. They are going to have to really think hard about taking someone who is durable and adequate over someone who is injured but has a higher ceiling.
According to PFF, QB hurries/pressures at the college level tend to be one of the biggest predictors of pass rush success at the NFL level. Of course it isn't the end all, be all, but the data shows a strong correlation.
That's not uncommon at all. Most HS players play both ways and often don't play the position they end up playing in college. If it wasn't until his senior year in college that he played on the DL, that would be a red flag.