It's very difficult to kick long and actually find the grass unless you utilise a grubber which is difficult to get a lot of distance with or you use the element of surprise and kick early in the tackle count.
With full backs and wingers dropping back late in the tackle count, and factoring in the amount of hang time in a big kick, it is generally fairly easy for the back 3 to cover any distance required to get to that kick.
Obviously if you have the ability to kick one of these spiral bombs like Matt Burton is capable of and other players like Adam Doueihi were able to do on the odd occasion, then defending players have lots of time to actually get to them, but then so do the attacking players which puts the defending players under even more pressure trying to catch a ball that is swirling and often moving away from them.
These are the kicks that are often allowed to bounce because they are so erratic and it is so difficult to predict where the ball will actually land.
I guess it is for this reason that these spiral bombs are becoming more common place as players begin to master the ability to pull them off because it is more difficult to find the grass instead of putting one down the throat of a defending player.
You will more often than not hear a commentator coming out and praising how good a kick is that actually finds the grass and beats a winger or fullback.
May not be completely correct but just my thoughts on attacking kicks.
