"Letting the club do the work" is much simpler when playing 1 Iron Golf clubs than playing conventional clubs due to the playability design elements incorporated. A couple of examples:

1. 1 Irons are the same length, weight, lie angle, offset, bounce angle, flex, etc. throughout a set which allows the golfer to use only one swing, swing posture, swing plane, and ball position for every iron in the bag. All of the irons within a set are virtually identical so that with every shot you make you are, in essence, practicing for your next shot. This makes it very easy to develop your full confidence with every iron and is the key to complete trust in a golf club. Once this complete trust is developed it is very easy to rely on your normal swing and simply "let the club do the work".
2. Conventional irons have progressively weighted clubheads from the #3 iron through the wedges. For instance, a typical #3 iron clubhead weighs 240gms, #4 iron 247gms, #5 iron 254gms, and so on in 7gm increments through the wedges. This means that a conventional #3 iron has the lightest clubhead feel within a set. The result is that 95% of all golfers try to overpower the shot with this lighter feeling clubhead while they tend to make more and more of a controlled swing as the clubheads progressively increase in weight. The main problem is that it is almost impossible to develop any sense of confidence or trust since every iron in a conventional set feels different (due to the clubhead weight variances as well as the shaft flex variances throughout a conventional set of irons). This results in the golfer trying to manufacture a shot rather than "letting the club do the work".

The notion of "letting the club do the work" and having complete trust in the golf club also reduces the tendency to use an arm swing which produces a weak shot and poor control. Once you have developed complete trust in a golf club your swing becomes almost automatic in that you let your body do the work of swinging the club, just letting your arms go along for the ride. This means making your swing around your body instead of out to the side as is typical in an arm swing.

Personally, all I try to do with any shot is to simply lay the clubhead against the ball through impact and let the design elements of the club make the shot for me. I never try to swing harder when I need a few extra yards as this typically leads to excessive arm involvement and a poor shot. The key is to trust your swing and most importantly trust your equipment to perform in the way in which it was designed.