Supportive

Made changes suggested by reviewer and resubmitting for review.
Yeah. I would just do this:

```ruby
def by_line
  return nil unless author.name && author.url
  "By #{author.name}, at {author.url}"
end
```

`try` is a rails construction & I try to avoid using it when I don't have to, or when there's no substantial gain. Everyone is comfortable with guard conditions, & often one line is better than two.