Maybe so, but take it from a Twins fan who watches each and every Twins game, passionately, religiously: for some reason, Johan is merely a B+/A- pitcher in April, short of his usual A+ stature as, IMHO, the best damn pitcher in the majors, most of the time.
All this is to say that early in the season, lines for games he pitches might be a little steeper than they should, and one should proceed with caution. That's not to say that he, and the Twins, will not win most of those games, but simply that April and May are usually an opposing team's best time to beat him, if at all, and therefore, a bettor's best chance to take a tag on him, if you've got the stomach for it.
Not that you'd catch me doing it, but.....