While commenting on a replay of Oliver Perez dropping a beautiful sacrifice bunt in the third inning, Ron Darling brought up a fundamental that I don’t necessarily agree with. Darling said that you should hold the bat at chest level, and if the ball is above it, you let the ball go because it will be a ball.
However, I have always taught (and been taught) the exact opposite: to hold the bat at the bottom of the strike zone, and let the ball go if it’s below. The thinking behind this, is that you are more likely to bunt the ball on the ground — and less likely to pop it up — if you move up to the pitch than if you move down to it.
Generally speaking, when bunting, you want to “catch” the ball with the bat, with the bat parallel to the ground or at slight angle that has the barrel slightly higher than the handle — this position gives you the best chance to put the ball on the ground.
Now, with that in mind, if you start the bat in a high position, and the pitch is low, you have a tendency to change the angle of the bat and drop the barrel too low — a position that promotes a popup. On the other hand, if you start the bat low and parallel to the ground, then raise it up to a pitch, you have a better chance of getting the ball on the ground. It’s all about angles and reaction time; if a pitch suddenly darts down — as many pitches do (sinkers, sliders, curves, splits) — you may move your bat too quickly and get under the pitch (or drop the barrel and produce an angle that causes a popup). In contrast, there is no such thing as a pitch that rises (the “rising fastball” is an optical illusion), so if a pitch is higher than the bat, it’s probably going fairly straight and it is easier to adjust the level of the bat. Even if the pitch is so high it is out of the strike zone, it might still be a good pitch to bunt — if you raise the bat properly.