The best reason not to open A Ank - Arm is because it means you've set up the board wrong. :)
I think it's funny that I'm getting a reputation out of this for being a player who likes to attack Austria as Italy. My plan for playing Italy definitely leaves that as a possibility, and I did so in 1901 with all three Italys I played in the first round. However, it wouldn't be fair to say that my plan consists solely of options for Austrian attacks.
@Lando, I felt that I did have success with these three Italys in Round 1; they ended up a 4-center survival (my side of the easy-to-hold stalemate line held), a 17-center draw (I had three 50/50 guesses for a solo and missed all three) and a 8-center draw (with Russia and Turkey still both viable).
@josunice: Like with all gunboat openings, the right answer is almost certainly a mixed strategy. As I've said, in the middle of the tournament, and given that I'm apparently unlikely to draw Italy in the next round, I feel it's...unwise to take this opportunity to introduce what I think is a new approach to Italy in gunboat. What I will do, though, is mention two factors that make playing Italy challenging, and that are the two main motivating factors for the approach I've developed. In other words, I'll remind you of the two main problems, but not give you my solutions for now. Fair compromise?
1) Distance -> advanced planning, the "fifth center" problem.
OK, you don't have to take much time to prep a stab for Trieste. But, in every other respect, you have this problem. To borrow a concept from chess, Diplomacy is a game in which you have to develop your pieces, bringing them to the front, before you can use them. This is most noticed as a problem for Turkey in the mid to late game, because it struggles to effectively convert builds into the power to acquire more builds. But, Italy has a similar development problem. After Tunis, any additional centers will require multiple units to take. Trieste is close at hand, but there are myriad problems with trying to take it, and even more with trying to hold it if you do take it. Greece is often Austrian if you haven't attacked Trieste, but if it's Turkish, you need to breach the Aegean to take it. Smyrna or Con are far further than Greece. On the other side, Mar is an investment requiring at least F GoL, and often a second fleet, because otherwise Spa S Mar is a line that France can easily hold.
In other words, getting a fifth center either requires an investment of several turns in one direction, with massive forewarning to everybody on the board (you might as well send an embossed declaration of war), with the one exception of Trieste, which you probably don't keep and is probably a poisoned pill. Solving the "fifth center" problem is necessary if you ever want to be a major player in the game. If a hostile Turkey gets a third fleet, it's necessary merely to survive.
2) You are in a bad position to gain from your attacks.
The good news is, when Italy jumps into an attack, there's a tendency for other powers to pile on, especially because they can usually see it coming (see point 1). The bad news is, they usually win. There are three possible realistic targets for expansion (sorry, Munich isn't one of them).
France: England and Germany will often jump in and help. Once France is gone, you're likely in for a fleet war with England. To get a good share of the breakup of France, you need to reach either Por or Par. England is much closer to Por, and Germany likely gets Par, with England also being closer.
Austria: When Austria breaks up, whoever keeps Budapest probably is the winner in the breakup. Russia is closer than you are, and Turkey is equally close.
Turkey: You'd better get Con, or you've gone all that way to pick up one center. Smy and Ank isn't enough because of what it does to you tactically. If Russia is part of the breakup, it's much closer to Con (and to Arm...). If Russia is dying in the breakup, then you need to pick up a third center as well.
To summarize:
There are three powers you can attack, and in each case, the key center is tougher for you to get to than your "allies". It would seem that it's a mistake to attack France unless you have a plan to get Por, a mistake to attack Austria without a plan to get Bud, and to attack Turkey without a plan to get Con+. And, you don't have the element of surprise. This is probably why Italy fares so poorly on the scorecard in gunboat. Having laid out the problems, I shall now refrain from offering solutions. :)