Peacetime training tends to become more unrealistic the longer it has been since anyone has been at war. This sort of thing has been going on since armies were invented. But in the United States this changed in the 1980s as new training methods were developed because of the realistic combat exercises held, since the mid-1980s, at the U.S. Army National Training Center (NTC) in the California desert. The NTC used a form of laser tag to accurately represent the ability of weapons to hit, and hurt you. When a soldier or vehicle was "hit", an alarm went off and the soldier or vehicle was taken out of action. Umpires (experienced officers and NCOs) wandered around making sure no one ignored their "you've been hit" indicator." Actually, it was hard to ignore who shot who, because all the "hits" were recorded for playback after the exercise. 

Out of this realistic NTC experience came the realization that current training methods weren't doing the job. The basic problem was that there were a lot of skills to learn to become really effective combat troops. In peacetime, this problem is made worse because too many senior officers can't resist adding more (often useless) equipment and (equally useless) procedures to the existing list of things to learn. There developed a pattern where troops were pushed through the training schedule fast enough to "do" everything. When troops and units were later tested to see if they had adequately learned their skills, the scoring was generous enough to paper over what had not been adequately learned. Everyone was in the same boat, and that's the way peacetime armies have always worked. That is, until combat comes along. But combat happens rarely for most troops, and the problem of botched peacetime training is often ignored in the wartime rush to fix everything and win the war. But NTC gave peacetime troops a taste of reality, and now lots of people were looking for a better way.

Combat units knew that they would regularly go to NTC and get a reality check, so the "Lanes" method of training was created by some officers at the 5th Infantry Division. The new method eliminated a lot of the training problems by forcing each step in training to be repeated (gong down the "Lane" as often as needed) until troops or units could really do each item. This became known as the "crawl, walk, run" approach.

This forced commanders to take a hard look at what skills, currently demanded by the existing training schedule, could be eliminates or scaled back so more time could be spent on items that would help at NTC, or a real war. With Lanes Training, when you learned something, you really knew it. This was particularly useful for reserve combat units, who had even less time than active duty troops. 

Another aspect of Lanes Training, also borrowed from the NTC, was the use of controllers (officers who observe and offer advice). The "Observer/Controller" (or O/C) is not from the unit undergoing training, and is there to note things that are not working and get the troops to discover problems, and solutions. This took the training away from working "by the numbers" to "what do we have to do to get the job done" by using an "After Action Review" (AAR). Here the O/C would assist the troops in honestly evaluating their training achievements. This is particularly useful for tactical training (how you move and fight in different combat situations), where troops in each unit have a different set of skills (speed, accuracy with weapons, Etc.) that can be used in different combinations to make the tactics work. Note that many combat units in Iraq are writing up AARs for their performance under fire. This helps spot mistakes, and fix them.

While Lanes Training was a simple idea (and had been invented many times in the past), it made units more effective in combat. This was seen first in the 1991 Gulf War. Many in the media liked to give most credit to the technology, but professional soldiers the world over knew better. American troops now got a lot more respect from their peers (who previously liked to dismiss American soldiers as "amateurs with expensive toys.") The later wars in Afghanistan and Iraq only confirmed what was first demonstrated in 1991. Generals in other nations began to clamor for more money and better recruits so they could be trained up to American standards. But this is hard to do. It takes lots of money to get the quality recruits, and then have them spend a lot of time and money training. Some nations, like Britain and Israel, do it (and have for a long time.) But many other nations only train their elite forces (commandos, paratroopers and marines) to the high standards. Being an effective soldier is more than having a snappy uniform and fearsome weapons.