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Differences between Lemania based caliber CH 27-70Q and CaliberCH 29-535 PS Q

While I have read many articles on the 3970, 5970 and the 5270, I have not been able to really understand the most significant changes between the movement used in the 3970 and 5970 (Lemania 2320 (2310?) based caliber CH 27-70Q) and the 5270 (Caliber CH 29-535 PS Q) .

Thus far, I know the following:

1. The CH29 is designed to be easier to manufacture and assemble than the Lemania-based CH27.

2. CH29 beats at a frequency of 4 hertz (28,800 semi-oscillations/hour) while the CH27 beats at 18,000 semi-oscillations/hour .

3. CH29 power reserve is 65 hours while CH27 has 60 hours.

4. The CH27 has the traditional triangular toothing, whereas the CH29 now feature new “profiles that reduce wear, improve efficiency, and prevent tip-to-tip collisions”.

5. Mesh depth is not adjusted with an eccentric cam as usual (CH27) but instead with a large, eccentrically shaped cap on the column wheel that defines the exact position of the outermost end of the clutch lever where the highest degree of precision can be achieved.

6. Further optimization measures for the CH29 include “self-setting hammers pivoted between jewel bearings, the direct synchronization of the brake and clutch levers, and the slotted minute-counter cam that prevents the abrupt blockage of the chronograph wheel.

These are the six innovations of the CH 29-535 PS Q over the CH 27-70Q that I know of.

However, since I am not that technically knowledgeable, I would be most grateful if the experts could explain, in a layman’s language, what these differences mean.

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