Collective wrote: it's almost as if I've told myself subconsciously '20 minutes is too long for you to focus - so don't even bother'. Then there's a feeling of restlessness (a classic I know) where I could be doing a million other things instead.
What's up Collective. Sounds like you and I are confronting similar issues. I can't sit still for the appointed 30 minutes. Something happened last night that gave me some insight into this dilemma. Quite by accident my usual timer went missing and so I decided to practice without it. I usually sit for 30 minutes timed, so I tried to emulate my normal practice absent the timer and without obsessing about hitting my 30 minute mark exactly. I just let it go. The difference in terms of quality was noticeable. It was almost as if the timer was a safety net and by taking it down I forced my hand to find some balance for myself. In a very spontaneous way I was in a better position to experience the restlessness as it is, without acting on it. I certainly did not expect the answer to be in less timing.