On the observe vs controlling. Observe and controlling in current Theravada are thought as something opposite, but I feel they can be read as the same verb – at least in most places. One has more passive connotation, the other more active. You can read it as “observe, and control if needed”. For control you need to observe. By properly observing you have [yoniso attention + sati] according to the teachings – and thus already kind of controlling what you observe.
Using the simile of the horses and the charioteer that Buddha used, like in the dhammada ch 7, that talks about arahants, verse 5 “he, whose sense are pacified like horses well-controlled by the charioteer …“. When one is in the first stages of the gradual training, during sattipatthana, the charioteer will have to exert a high degree of control at all times, the mind and body are wild, therefore he will need to strongly pull the reins over and over again. When one is really advanced in the training, the charioteer just need to keep watch over the tamed and pacified mind and body, holding the reins with a relaxed grip.
Even in daily talk, “control the kid!” and “observe the kid!” has the same meaning: in both phrases you are being commanded to watch that the kid behaves properly and is safe. If the kid is wild, you may need to hold the hand and control it directly. If the kid is well behaved, you can let him go free, and just observe he doesn’t go further from you. Since most of those kind of instructions are delivered to bhikkus, my guess is that observe is used, they already got a base. However, over the canon you can see the Buddha using “observe the mind”, “keep watch over the mind”, “control the mind”, and similar to refer to the very same fact that one must take care that the mind behaves according the dhamma.
On the breath. I feel that use the breath can be useful, not for the insight it provides, but because is a kind gross “accelerator pedal” which is tied to the mind. “The mind is extremely subtle and difficult to grasp, alighting on whatever it pleases. It is good to tame the mind, A tamed mind brings happiness” (dhammapada). I feel that the main benefit of watching the breath is to help oneself to not lose sight of the citta and the thoughts that arise and ceases without being dragged by them. In other words, to help you to recognize the working of the mind. Not sure what Lal would think.
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