would the securing wire not wear away every time it passes over the sprocket teeth?
The safety wire securing the clip wire will never contact the sprocket. The sprocket only comes in contact with the rollers and the inner links. There is a gap provided by the inner link that acts as a spacer to the safety wire which will not allow the wire to touch the sprocket (if installed properly).
Edit: Just safety wired the clip on my Grom. This photo shows the air gap between the wire and the sprocket:
If there is a 1 in 10,000 chance of the link failing, you are living on borrowed time!
Then we are all living on borrowed time. There is always a chance a chain can lock up or break at any time and not be the fault of the master link. Obviously a quality well maintained and inspected chain/sprocket combo will provide better odds of preventing a premature failure.
You spend all this money on having a safe bike, yet this is an obvious flaw that some people put their trust in??
I spent an hour or so reading all over the ADV forum, the link posted above by A2RON and others and found a mixed bag of information. The number of folks stating c-clip disappearances and failures are less compared to the folks who have logged many thousands of miles on them on road and off.
I am in no way stating the c-clips are better than properly riveted, nor am I saying they are crap. For those who have lost clips, we don't know the history of the install (possibly backward), or possibly spread too far during initial install. From watching how to videos, they are not super easy install and can be bent if not careful.
Since my Grom came from the factory with a c-clip, and it making ~9HP, I am not too concerned with a c-clip failure. For extra insurance, I just wired around my c-clip today and I will not have any worries of losing it.
When the time comes to install a new chain on my Versys, I will either rivet the masterlink or safety wire the clip.