Yes there have been lock failures and i have already documented mine several times.
If I were ever to buy another IL gun, as long as it shows no signs of binding then I would leave the lock.
as for removing the flag to insure it doesn't fail or in my case to return the gun to a functioning state, If I have to use it in self defense, the last thing I am going to worry about is if a lawyer is going to exploit the IL.
If people are so worried about little things like that, then maybe they shouldn't be carrying a gun and instead carry there cell phones and call the cops.
this whole argument is getting really old.