She goes into some interesting analysis in the article - eg
Of the 120 rapists in the sample, 44 reported only one assault. The remaining 76 were repeat offenders. These 76 men, 63% of the rapists, committed 439 rapes or attempted rapes, an average of 5.8 each (median of 3, so there were some super-repeat offenders in this group). Just 4% of the men surveyed committed over 400 attempted or completed rapes.
She goes on to say that of the 120 admitted rapists, only 30% used force, the rest zeroed in on drunk victims and used coercion - they knew it was rape, they admitted they knew it was rape, but they used tactics that made it virtually impossible that they would be convicted. It's sickening, and certainly makes me think that 1 in 4 is likely to be an underestimate.
I consider myself fortunate that any time I've got totally legless with a bloke, they've take no for an answer, or I've had drunken, but consensual sex (and yes, women know the difference)! Unfortunately, you don't need to be drunk for a boyfriend to refuse to stop, and that has happened