Hi Gareth,
I didn't see this thread until your recent tweet about it. You make some interesting observations.
1. I really don't feel like I am suppressing thought when I meditate.
That's partly my point. Suppression can be deeply habitual and / or extremely subtle, which makes it hard to 'see'. I don't feel like I'm suppressing my thoughts either. However, the fact that my mind can become so quiet in meditation (whereas it is not usually quite so quiet outside meditation) suggests that thoughts may be being suppressed to some degree.
2. I notice the thought stream, and that very act seems to dissipate it.
Yes. Noticing the thought stream tends to have a suppressive effect. It may not feel like suppression. We may not even think it appropriate to call it suppression, but the fact is, thoughts are somehow suppressed. They dissipate, dissolve or disappear. This doesn't happen normally, for example, when we're not fully conscious of what we're thinking about.
I'm not saying that suppression is necessarily a bad thing. Just that it's happening. More importantly, it can be useful to meditate with the intention of letting thoughts go on, rather than trying to observe them. People often feel like there is something wrong with getting 'caught up' in thoughts. But when you meditate without such an aversion to getting caught up, thinking often becomes less of a problem. You can also begin to see your patterns of thinking in a more lifelike (less interrupted) way, and it's the understanding that stems from this intention — rather than the act of observing or witnessing per se, which leads to a more natural quietening of the mind.
3. I really don't see how I could 'not notice' the fact that I am thinking.
Can you be more or less aware of your thinking? Can you always say with confidence what you've been thinking about? Have you ever fallen into a reverie and 'woken up' some time later, or driven or walked somewhere and 'missed' part of the journey because you were thinking on 'automatic'? Aren't these all instances in which we don't notice (fully) our thinking?
I'd be interested to hear your responses (and hope my response hasn't sounded too didactic).
I agree with Peter's comment about the possibility of approaching throughs (all of our experience really) with a very light touch.
And I would argue that there is no need at all for beginners to return their attention to the breath. In fact, I would say that the instruction to return to an "anchor" can potentially cause a lot of struggle and difficulty (depending on the student). My approach has been to invite students to focus on simple sensory experiences (breath, body, sound, etc.) but to stress that this is a choice they can make, rather than the only approved or appropriate response to thinking (or any other kind of so-called distraction).
I used to teach a more traditional 'anchoring' approach, but have found that my students have better results and far less struggle when they use the breath as a rudder, rather than an anchor. That is, they return to the breath only in those circumstances where their attention is drawn naturally there, or when they feel the need temporarily escape some discomfort (either mental, emotional or physical).