Coitus interruptus has a failure rate of 15%-28% per year, 4% when used perfectly. In comparison, condoms have a failure rate of 10%-16% (2% when used perfectly).

You were perhaps aiming for a sound-bite, but saying "It works in very few cases" is inaccurate.

I think it made my point quite nicely. Piracy works in a very small percentage of cases. We shouldn't be clinging to this fact and saying that it's an effective way to market and advertise.