Rookie

I'll just share my opinion on the matter, for what it's worth.
Now first off, I prefer All Pro difficulty for one reason. That being there are no ratings boost whatsoever, in previous Madden's you could see during preplay the different matchups and notice that All Madden was in fact altering ratings. On All Pro if 'x' player has a rating of 85 speed, he has 85 speed.
For the questions listed
1. Is Robo QB alive? Yes and No, some games you will have a good QB go 12-13 passing to start but you also get games that guys start off poorly. For example, I played the week 4 Matchup between Carolina and Houston. In that game, Watson started 1-6 for -2 yards. But later in the game he was 23-34 for over 250 yards. So if you give All Pro time and don't judge off of 1 quarter, you will have games that vary. Guys will have great games, poor games, bad start but finished strong type games, great start but fall off type games.
2. Yes CPU teams use their X Factor abilities. I've seen plenty of QB scrambles, crazy jukes, hit sticks, great coverage etc. on default All Pro.
All Madden can be great, I played on All Madden for a long time when I was younger. Lately however, I get great games on All Pro that are just fun to play which is the most important part.
I would rather have a fun, fair matchup where you still need to play smart to win than to have a slightly tougher matchup that is obviously just downgrading your team a little for a challenge.
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