On Having No Head (D. E. Harding) - Help me understand

I've been interested in meditation for some time now - tempted by the insight into the human condition that it purports to offer - but I haven't yet experienced any kind of 'breakthrough' moment that has brought any clarity, let alone insight.

I have read Sam Harris's Waking Up, and have done some of the course in his app. The most I've been able to achieve is to observe (and subsequently limit, control) getting angry. This has proven pretty useful but doesn't feel profound.

Anyway, I'm now about half way through D. E. Harding's On Having No Head, and I am struggling with it.

I keep telling myself to stick with it because what he's saying might become clear, but I'm finding the reasoning behind it to be wilfully obtuse at times. I fear I'm exposing myself as some kind of idiot in even asking about it, but can someone help me see his point?

He talks about looking at what you're pointing at. Makes sense. I can see those things, therefore they're there.
And then to point at your face. You can't see that. Ok. Makes sense. I can't see that, therefore it's not there?
I can vaguely see a blur of my nose, but that isn't anything worth worrying about?

But I can demonstrate that it's there. I can photograph it. I can look at it in a mirror. I can touch it and feel it (and it can feel).

I feel like I'm the fool staring at a metaphor and screaming about it not being real but I can't see the bit I'm missing!

Does anyone have any insight they can share?