In golf, weirdly, the hands sometimes get bad press. "He's a handsy player" is almost seen as a slur on technical prowess. Many coaches also talk about wanting the big muscles of the body to control the swing, and wanting the "take the hands out of it". It might sound appealing mechanically, but if these influences lead a golfer to pass over the vital role our paws play in motor skill, it will hold them back.
The way in which we access an effective self-organised swing, is very much led by the hands. Firstly, the most obvious point is that they are the only direct contact with the club, so they are intrinsically involved.
Secondly, we are dextrous creatures, and so many of our motor skills are informed by the effect the hands need to create. One of the defining moments in our evolution was when our ape-like ancestors learnt to stand upright. It freed up our upper limbs and from that point on there was no task we couldn't turn our hand to, literally. Ever since, the human brain boasts incredibly sophisticated neural connections between brain and hands. This relationship should be leveraged when learning a sport like golf.
Examples
From your own experience consider how it might work. Imagine having to push open a heavy door. We start by placing our hands on the door, and when we discover more effort is required than we were expecting, we re-organise our body to exert more force through our hands.
The hands almost act like a reconnaissance mission, probing out what's required, and then enlist other parts of the body if the task needs a bit more oomph.
Similarly, hammering a nail might start with a couple of exploratory taps, to get your eye in, see the direction of force required to get the nail in at the right angle, then building up to bigger, more powerful movements involving more of the body. You might also even adjust your stance after a couple of attempts to better deliver the blows you need. The sequence being: the brain sizes up the task, the hands help prepare, the body gets involved.
The task of golf
Delivering a clubface effectively at speed involves much more precision than these two examples, but the task and process is similar.
In golf our hands can inform the body about the very particular forces are needed to be exerted on the club.
In task-led learning exercises, we can use one hand and small movements to help the brain prepare for big, organised movement.
Which hand is smarter?
Quite often in swing faults, like a disjointed takeaway for example, at the root of it is one hand working in opposition to the other.
When working with clients, I often investigate if one hand is better at golf than the other. By doing a few drills or task one handed, normally you see one that naturally moves the club more appropriately than the other. More often than not, it is your dominant hand, but not necessarily.
I am particularly interested in seeing which hand is most effective at delivering a square blow at impact, informing the body to self-organise as a team. I use an exercise called "Palm golf" to explore this.
Bi-lateral transfer
Once you've established which hand best performs the tasks, you can use this to help the other. Bi-lateral transfer is the transfer of learning from one hand (or side of the body) to other. By letting the smarter hand lead the way, it can educate the other how to compliment (rather than sabotage) the movement.
Whilst we want both hands to work together in a swing, there is no harm when learning or refining your movement, for one to take the lead.
Distinction
When we talk about letting the hands lead the learning, we are not disputing good sequencing in the swing. Example: commonly, we might expect to see a subtle shift in ground pressure to the lead foot as the first sign that the backswing is about to end, and the downswing is coming next. However that shift is often a by-product of an effective self-organised swing, learnt initially with the hands.