I think it's just phrased in the usual IAM fashion - they advocate driving defensively, with observation and anticipation paramount. They've just taken what they'd advise for a driver [1], and put it in a cycling context.
Their definition of defensive would be considered to be "aggressive" or, at the very least, assertive cycling by many less well read motorists.
As for putting the onus on the cyclist, that's their ethos for motorists too - they consider that most accidents are avoidable, if you've had a near miss, you need to improve your observation, anticipation, road positioning, appropriate speed, skills, etc.
For example, you nearly hit a child running out into the road after a ball. You missed the clues - children playing by the roadside, visible feet under the parked cars, ball rolls across the road = slow down, cover the brakes and prepare to stop if necessary.
They're not thinking "victim blaming", they're advising the one in command of the vehicle, and have companion advice for the advanced motorist, as for the "advanced" cyclist.
I'm pretty certain I've heard the same advice from driving instructors, lorry drivers, and cyclists - assume the other road users are idiots and drive/cycle "defensively" to protect yourself, your no claims bonus, or your vehicle from their mistakes!
Robert
[1] Yes, including the hi-viz, recommended for when you're an "accidental pedestrian", such as a breakdown