Nice idea however I don´t know how he would like to put that board with the 16F628A in a watch unless he doesn´t want to wear a big battery pack around his right wrist. Lovely Fairchild displays btw.
I built a 230V clock which is actually hanging in my staircase with exactly the same 16F628 about 6 years ago. The prototype of this clock is working with TTL chips, mainly 7417 decade counters and 7400 NAND gates. The LEDs are sitting in translucent bars and balls. A friend of mine from Köln always tells the time when he visits me. So he shows me that he is intelligent enough to read it (not that easy) and that he has been remembering how it works.