First of all I might point out that the famous dictum of "form follows function" itself has never been used by the Bauhaus movement, but must be credited to the US architect Louis Sullivan in 1896. However, it is clear that the Bauhaus movement, like all other modernist design movements, closely followed the philosophy behind the dictum. There is a very good article accessible online:
But back to the watch: I agree with you that the specific case design can easily be justified by the dogma "form follows function", but in my humble opinion, this dogma has been fully forgotten when the dial was designed. What is the function of a sports watch? To be very solid, and to offer a display of the time that is easily and quickly legible under even adverse conditions. What is the function of a chronograph? To be used as a stop watch. What is the fucntion of a sports chronograph watch? To offer the functions of time display and stop watch reliably and easily legible under even adverse conditions.
While I am sure that nobody would dare to challenge that the watch(es) shown fully meet the former condition, since it will be difficult to find a more solid and shock-resistant mechanical watch (inhowfar this really offers a distinct advantage in practice, remains to be seen in the future), I personally doubt the fulfilment of the latter requirement:
Especially the Extreme chronograph makes it difficult to read the elapsed time at a single glance, since it is very likely that one will not find the stop second hand, among the confusing array of 24 hours hands (however, I admit, this problem seems to be much more present on the platinum version, while the steel version seems a bit better to my eyes). The minute counter's increments of two minutes is another problem. I think that many, if not most owners of watches with pointer calendars on a subdial will agree that it is very difficult to read the calendar at a quick glance. The numerical values all look the same, and it is not easy to quickly determine whether the hand is directly on a figure or between two figures. In the experience, chronograph minute counters with ten or fifteen minute increments (with small markers between) have proved reasonable, while still inferior to the rare system with a central 60 minutes counter hand. Why JLC now adopted the worst increment system, is beyond my understanding.
The hour counter solution with the rotating disc is very intriguing. However, also here, I think the presentation is not optimal. The figures printed onto the disc are too high, and at the same time to narrow, to be conformed to the disc diameter. This makes the individual figure appear abstract, strange, and disproportionate. The result is that the brain is not able to understand the number shown intuitively, but has to "study" the figure, in order to understand it. As an example from practical typography:
The same happens with the numeral display of the hour counter disc: the figures are difficult to read at a glance, and additionally, the small radius above the pointer's arrowhead makes possible only small steps between the figures, which again results in a problem to see whether the pointer shows eleven hours elapsed, or eleven and a half.
Finally: There are too man white spots dispersed on the dial of the Extreme chronograph: The white date window between four and five, and the flashy small second disc distract from the hour and minute hands, which - in comparison - are a lot less conspicuous.
Please note that my critical remarks mainly are directed against the Extreme chronograph, while I think the Compressor Chronograph to be a bit better, at least by lacking the confusing 24 hours hands, and the white date window being located in the place of the hourmarker at six. And by no means would I dispute these two to be highly attractive watches, which they are. I like both of them. What I am disputing, however, is that the design of their primary machine-human interface, the dial, can be interpreted as following the dictom of "form follows funtion".
With best regards,