I've read countless articles regarding both swing types and I must say I'm partial to the conventional swing type. But with that said, I want to explain the fundamental differences and key benefits of each swing type. Both swing techniques can be effective respectively, but one is more designed for accuracy, while the other, distance.
Address
Conventional Swing
Your body weight should be centered between your feet 50/50, and also be resting on the balls of your feet (not on your heels or toes). When viewed from front on, your lead shoulder should be higher than your trailing one, tilting your spine away from the target; ball position should be centered or slightly ahead. Viewing down the line – your arms should be hanging close to straight down from your shoulders, your knees and elbows should be relaxed and unlocked and your lead arm should be visible above your trailing one. Your shoulders hips and feet should all be parallel to your target line.
Stack & Tilt
Your body weight should be slightly favoring your lead foot on about a 55/45 split. Much like the conventional setup, your lead shoulder is higher than you trailing one – but this is mostly to do with the fact that trailing hand is lower on the grip than the other. Despite this, your spine should be straight and perpendicular to your knees, shoulders and feet. When viewed head on your shoulders should be stacked over your hips – meaning if you drew a straight line down from either shoulder, it would intersect each knee. Both your feet should also be slightly flared out.
Backswing & Transition
Conventional Swing
Your backswing extends back as your body begins to coil – your weight slowly transitions to your right side as your wrists begin to cock. As you reach the top of your backswing, your weight is transitioned to about a 70/30 split on your back leg with most of this weight positioned on your trailing foot’s instep. You’re fully coiled, with most of your body behind the position of the ball. This is an incredibly powerful position and you see it among most other ‘loaded’ sports positions – baseball, hockey, sprinting.
Stack & Tilt
The stack & tilt’s backswing remains very centered or leaning slightly to the front foot in terms of your body weight (see the image for a good visual view of this swing technique). Your shoulders rotate circularly around your spine, as this happens your lead leg will bend and your trailing leg will straighten… this leads to a spine angle that is slightly leaning towards the target at the top. Your head and body is almost directly in line with the ball. From this position there is no need to shift your body weight again.
Downswing
The stack and tilt method considers the conventional weight-shift to be a nuisance because you have to shift the weight back forward on the follow-through; which leaves a lot of players behind in the dust. This is where you get to see the fundamental difference between these two swing types. The conventional swing is a distance oriented motion – whereas the stack & tilt is a balance of distance and accuracy (based on the simplicity and repeatability of the swing).
Conventional Swing
In the conventional downswing, your arms should drop downwards as your body begins to uncoil and your hips open. As this occurs your weight is shifting quite dramatically from your hind leg to your front leg, this move creates a lot of power, although, yes, it can be very difficult to coordinate. At about hip height, your wrists should begin to un-cock releasing a lot of stored energy as you come into impact. Your body and head should mostly be behind the ball at impact. This position helps to create crisp contact, and especially with the driver – makes sure the ball is being hit on the upswing. On the irons, ball positioning and club length ensures the ball is hit with a descending blow.
Stack & Tilt
In the stack & tilt swing the downswing starts with the lead hip sliding forward, which tilt the spine away from the target. The slide from the hips puts your body and head ahead of the ball to encourage a descending blow. The lead leg straightens slightly which causes the body to lift upwards allowing the hips to uncoil smoothly. The wrists then un-cock in the same general position as with the conventional swing.
Follow-through
Conventional Swing
The conventional follow-through continues the weight transitioning to the front foot as the arms swing slightly to the inside due open hips. This move is criticized by stack & tilt advocates as proof of coming over the top (out to in swing path). If during the transition, your hands make the first move down; your swing path should follow an in-to-in direction, which is perfectly fine and effective.
Stack & Tilt
The hips continue to thrust forward, resulting in a “reverse C” position, with the body facing the target. As your body straightens, the spine leans away from the target, but your weight is still sitting on your front foot with a 90/10 split. Keep your arms rather extended, with a slightly shortened follow-through.
I hope this clarifies the major differences between these swings… and guys don't be afraid of straying away from convention, golf is a game that shows of individuality more than any other. Be yourself
out there!