Is it possible FTF's may begin to occur after some appreciable wear?
Yes, for a number of reasons, the most common of which are:
1. Springs may take a set and weaken.
2. You may get a lot of hard primers in any brand of primers or commercial cartridges.
3. The cylinder may develop endshake (back & forth movement, as opposed to rotational movement) which increases headspace.
4. Dirt or fouling may invade around the lockwork.
The factory builds in a certain safety factor with their heavy springs to insure that in any emergency the revolver will function and fire - no matter what. When the springs are lightened this safety factor is reduced or even eliminated. Some think they can beat the odds and still get a lighter pull by only reducing the rebound slide (trigger) spring and not the main (hammer) one. However a reduced rebound slide spring can tie up the gun in double action firing if the trigger dowsn't move fully forward, or the hammer doesn't rebound, or the shooter starts to pull the trigger again before it is fully forward.
A lot depends on what you are going to use this revolver for. If it is strictly a range gun I wouldn't worry - but if you get a misfire keep the muzzle pointed downrage while you slowly count to 10, because you may have a hang fire. Also if the springs have been altered you may have a single action pull that's too light to be safe.
If the gun is used, or kept as a defensive weapon, I would stick to the factory springs, because unquestionable reliability is more important then anything else.
Perhaps the answer is best to have two revolvers, 1 for her and 1 for you.