clip links can come off (snap) at the clip if say a rock, pebble....excess dirt gets packed up in there. Not highly likely...but it can happen.
Wouldn't recommend tieing anything on to hold the clip on...as it may interfere with the natural flow of the chain.
The positive with clips is that you can easily take out a link or how ever many when/if it comes to that.
Also - sometimes people will put the clip on backwards...i think there are arrows or dots or something that you match up to ensure it's on right and pointing in the right direction. If its put on wrong...your bike will tell you quick
Rivet style chains are obviously your best bet...but once the chain is worn and adjusted to the max on the bike...it's pretty much done. You can get a rivet push tool....but one slip and you'll end up buying a new chain anyway.
Guess it all depends on where you ride, how you ride, and when you ride.