Proper reconnaissance is as essential before any game that you play as it was for General Lee before Gettysburg. As you likely recall, Lee was without his "eyes and ears" at Gettysburg and suffered immeasurably as a result.
While it is nice to assume that your opponent has chosen a well-balanced scenario for you to play, there is a strong probability that they have not. Maybe it is on purpose, or maybe they didn't look too much at the scenario, or maybe they just clicked on any scenario whose description looked interesting and proposed it to you. In whatever manner the scenario was chosen - should you just accept it without a pre-battle reconnaissance?
The answer is "No."
While it is true that it is fun to play games and that winning is not everything, it sure makes a game more enjoyable if both players have a fair chance to win the game from the start. Games which are very lopsided are more likely to lead to player disagreements and friction, slower return rates, and potentially create a game in which neither player enjoys nor wants to finish.
Let me give you an example of why it is very important to scout beforehand. This is one of hundreds of examples I could give.
Below we have a actual scenario description from the Overland Campaign.
Description - Lee pushed his army into the Wilderness to disrupt the Union Army's scheme of maneuver, and he succeeded. Rushing east on the Plank Road, A P Hill's Third Corps fought a running battle with the 5th New York Cavalry, and as the scenario opens is about to capture the Brock Road Intersection, which would have split the Union Army, with Hancock's Second (US) Corps isolated to the south. Realizing the emergency, Meade has sent three brigades of General George Getty's Division of the Sixth Corps to secure this vital objective. Getty must hold on until Hancock, recalled from his projected sweep around the Confederate south flank, can come to the rescue.
The scenario description above is EXACTLY the same for the following three scenarios:
101-640505: (H) Brock Intersection_A1
102-640505: Brock Intersection_A2
103-640505: (H) Brock Intersection_A3
One of these scenarios is bad, another good, and another great. But how would you have any idea which was which without scouting them beforehand?
Scenario 101-640505: (H) Brock Intersection_A1 is the bad one in the group.
There are 32,109 Federals in this scenario against just 13,369 Rebels. Further, the objective hex at the Brock Road intersection is 200 points and is squarely on the "Union" side of the map. By taking this easy objective quickly the Federals are already within 50 points of a victory. Considering they then have 24 turns to attack you with far superior numbers on a small board, with plenty of time to outflank you through the woods, you are doomed.
But then Scenario 102-640505: Brock Intersection_A2 is an improvement.
Here there are just 14,346 Federals against 8,819 Rebels. There are also fewer turns in this battle which makes this a very fun, challenging, and overall acceptable scenario for both players. But the Yanks will still have that Victory Point advantage thanks to the Objective Hex so close to their side of the board, and it might be hard for the Rebels to gain a victory here. But if you are looking for a bloody, fast, and fun game... here you go.
Lastly, Scenario 103-640505: (H) Brock Intersection_A3 is the best of the three "identical" options.
Here we have the same exact setup, and numbers involved, as in the scenario listed above. The difference is that the battle lasts three turns longer. This extra hour of play time allows for a little more time for maneuvering and battle. This setup practically guarantees a bloody battle where both sides are challenged and have to make wise choices. The same "victory point dilemma" exists here as in the other two Brock Intersection battles but it is what it is sometimes. A fun setup and worth playing.
Above you have a great example of why it is important to view suggested scenarios you are asked to play before definitively committing to a game. My advice is to take the time to open the proposed game and look at the objectives on the map, their point values, the beginning Victory Dialog screen, and also the disposition of the forces on the map. Look for scenarios which suit your tastes, and which are also agreeable to your opponent.
Before investing the days, weeks, or months, into a one-on-one game with an opponent, you should make sure you are going to be enjoying a fun and fair game.
Some Members prefer Meeting Engagement scenarios, others prefer set-piece battles where the units are already deployed, still others might enjoy only historically based scenarios as opposed to alternate history scenarios. Try them all! Have some fun. But taking the time to scout a scenario beforehand is a must.