I got the watch in early Feb ’16. Forgive my mixing of metric and imperial, but that’s how I roll. 
SOME INFORMATION:
I’ve run 5k, at least 4 days each week for years
I’m 6’2” 200lbs
My comfortable stride is consistently 1.2 to 1.23 meters
My comfortable cadence is 148-155
My normal 5K HR is 149-156 … up to 170 going up big hills
My average speed is 7 mph
My best 5K time is 26.06 – 7.2 mph and 155 cadence. HR was 155-170
My goal is a 25 minute 5K.
So, what is cadence lock exactly … ?
Is my HR locking with my cadence, or my cadence locking with my HR?
My HR and cadence numbers have a significant overlap … am I experiencing cadence lock or is it just coincidental that they overlap?
How do people get cadence of 180+?! I have tried reducing my stride, but it feels so wrong (I actually injured myself trying this … strained a muscle on backside of knee). The only other thing I can think of is simply to run faster, but I’m not sure I can maintain too much faster than 7.2 mph for an extended 5k run … maybe a bit I suppose. However, the faster I run, the longer my stride becomes.
I have good running form, front to mid-foot strike. Until fall of 2015, I ran barefoot for the previous 5 years, and believe me, you learn good running form doing that or you pay for it!
Whew! Sorry, that’s a lot of questions! I’m just trying to get more scientific with my running. Until I got my watch, I was more like Forrest Gump … I just ran without thinking too much about it.
Max