Throughout the TI forums, we find references to how the elites swim and whether or not Total Immersion needs to change its teachings so that we all drive towards swimming like Michael Phelps and like company.
One of those contentious topics is the spearing angle. I replied on one of the forum posts with this:
Like all things taught in TI, spearing angle, depth and width, is dependent on so many factors:
1. Skill level of the swimmer
2. Natural body buoyancy of the swimmer
3. Fatigue level
4. Water conditions
5. Drilling vs. Training vs. Racing
It isn't entirely accurate to say that one way is the best way. After all, we humans are of different body sizes and shapes, our fitness levels differ, our brains are wired differently as are our nervous systems by the time we attempt our swimming.
Throwing out some observations on spearing:
1. Drag in part is caused by the amount of frontal area you present to the direction of travel. That means that when you spear deep, you are presenting more of the area of top of your arm to the direction of travel and thereby produces more drag than if you are spearing horizontally.
2. Spearing deeper can improve your body's balance in the water. For drilling, it can be a much easier experience if you spear deeper as you are generally moving slower and lower speeds will cause your butt to drag a lot more readily than at higher speeds.
For example, I used to struggle with kicking across a pool in skate position. It wasn't until I speared deeper than I normally do while swimming, that I realized that my body was higher in the water and kicking actually propelled me more.
So spearing deeper (in conjunction with other things like weight shift forward and reducing the time that your arms are lower than your head) will help improve body balance.
3. At higher speeds, you can spear more horizontally since your momentum helps you stay higher in the water.
4. Spearing higher also means you can execute an early vertical forearm easier since your elbow is already high.
5. I would definitely say the drag produced by a lower spear is pretty inconsequential compared to the drag produced by your lower half of your body dragging through the water. So if you spear more horizontally before you have mastered good body balance in the water, you may find you're struggling a lot to gain speed but this speed could be regained by spearing deeper because you're counterbalancing your butt dragging.
6. Your fatigue level will drive how deep you will want to spear. Swimming with EVF can be very tiring over long distances. You may want to rest and spearing deeper will allow you to minimize drag, maintain good body balance, and decent speed while you rest.
7. Pool water conditions are very sedate and consistent. Once you jump into the open water, all bets are off. You will find that waves (and other swimmers running into you) will constantly be challenging your balance. You may find that in order to maintain balance and some control in certain water conditions, you'll have to spear deeper (and potentially wider too).
8. Your skill level in learning TI swimming can dictate how deep you'd want to spear. Generally, beginners in TI (or in overall swimming) will want to experiment with the depth (and width) of the spear to figure out what works best for them. This is like learning to walk before you run; you start with basics and then move up in skill from there, as you master elements before them.
Spearing deeper for beginners will help improve their experience of swimming because their body balance is improved; with better body balance, there is less struggle in the water. Once basic body balance is mastered, then they can learn more advanced TI concepts which generally mean advancement to body coordination in kick/hip/spear and then on to EVF.
But if you are of a body type/shape which has less natural body balance and you try to advance too far by spearing too horizontal, most will find that there is a lot of struggle and they may not know why or how to improve, except to back off and start from the beginning. How impatient we humans are to improve!
9. Spear depth/width will also vary if you are drilling, or training, or racing. When you drill, you practice focal points and some of those will mean deeper spears. When you train, you will want to swim laps with different spear angles to get used to swimming with that style over time. When you race, you'll want to go for speed and hopefully you'll have prepared properly for a spear that will minimize drag and maximize your ability to generate speed.
Flexibility in spearing is just one of those elements of swimming that should be mastered as a goal.
10. Ultimately, practicing all depths (and widths) of spearing will prepare you for the varying conditions of open water racing, and you can remain relaxed in the ocean even while 3-6' waves are battering you. If you start getting distressed or panicking in the ocean because of rough conditions, you will waste energy doing something unfamiliar which is bad. Practice in the pool with different spear angles will help prepare you for the unexpected in open water.
11. People who swim don't all have the same goals. Some want to just enjoy being in the water and swim without feeling like they're going to sink and drown. Others want to experience the joy of swimming from Alcatraz to SF and say they did it. Still many others want to have the race of their life at the next Master's competition or Ironman. Dependent on your goals, you will find that your spear may also reflect what your ultimate swim goals are.
A deeper spear involves swimming in a more relaxed fashion while still retaining a lot of propulsion. If you want to enjoy swimming in a pool or lake for fitness or fun, then you may be just fine mastering TI with a deeper spear. And being like Michael Phelps isn't your goal so why bother trying to practice mimicking his form?
But if you want to have the race of your life, maximizing speed on the swim leg of your next Ironman, then maybe you'd want to try to master the minutiae that generate that last microsecond of speed, including those elements of spearing which accomplish that.
All in all, spearing is a much more complex topic than anyone can realize. I have found it worthwhile to explore the limits of that topic and think that TI provides the best place for that discovery and learning to be accomplished.
ADDITION FROM THE TI FORUMS:
I forgot about injury reduction/prevention. Whenever we raise our arms out of the range of straight down to some angle up but forward of the head, it puts stress on the shoulder joint. It's in a disadvantaged position relative to the muscles and tendons and if you try to flex there, the likelihood of injury is much higher.
So if you spear horizontally, the arms are in the "over the head" position and thus in an unfortunately disadvantaged position relative to our normal ranges of motion. Spearing deeper means your arms/shoulders are in more advantaged positions and our muscles and joints can flex with greater utility.
Overextending your arm out of the shoulder socket can also put stress on the shoulder while stroking. So spear, but if your shoulders are beginning to hurt, you may want to practice not extending so far. It reduces the total length of a stroke's pull but better that than wrecking your shoulder joint. However, not extending so far means you can focus on other aspects of your stroke to increase speed, like coordination of your body/hip rotation/2BK to add authority to each spear, versus extending your arm so far and injuring it.