I have had several p*** where the hole in the tube is right in the
middle of the mark the end of the tyre liner leaves on the outside of
the tube. It only seems to occur when the tube is a bit too small for
the tyre. I suspect this means the tube must stretch to fill the
tyre. Hence the outside of the tube in tension making it more
susceptible to develop a hole by rubbing against the end of the tyre
liner. I have had this problem even when the tube in question was
supposed to fit in the tyre (according to the tube manufacturer).
Recently I have started ignoring the recommendations on the side of
the box the tube comes in and making sure the tube is as close as
possible to the size of the tyre. Since then (~5,000 km riding) I
have not had one p***
Peter Damm