You're absolutely right, it's like a switch flipping in the brain.
Maybe a way to get there, or to try to explain it in a different way would be: You have to hate "having the item in your todo list" more than "doing the task".
I know I do. It's annoying to "carry" that todo item in my head all the time, with its danger of forgetting it, or the need to note it down somewhere, then remember to check the somewhere... So I know I'l feel liberated when I do it.
Yes, on the face of it this applies much better to "pay that bill" than to "write a book". But you'd be surprised. Soon you won't think of yourself as a procrastinator, you'll feel like someone who takes charge and does stuff. You know what people like that do, apart from the small stuff? The big stuff.
Did try that very early on (spoiler alert: it didn't work), and it's curious what mechanism my brain developed to neuter this trick.
One, in line with what GTD book teaches, writing down a task is very liberating experience - indeed, the act of writing a task down feels almost like doing it, so it drains the pressure to actually do it. Two, once the mental weight of a full todo list reaches a certain stage, I instinctively shy away from looking at it. The degree to which this happens subconsciously is probably worth a paper in a psychology journal; I'll instinctively stop opening my TODO files, my Org Agenda, and if I write the tasks down physically (e.g. on whiteboard), after a while my eyes will just gloss over it and essentially ignore its presence in the room.
To combat this, I started cycling through TODO stores - every other month or three I jump between .org files, bullet journal, issue tracker tickets, whiteboard, notebook, paper calendar, electronic calendar. The "freshness factor" seems to be working somewhat, but I still can sometimes go two days before realizing I have an organizer open on my desk with tasks already late.
Maybe a way to get there, or to try to explain it in a different way would be: You have to hate "having the item in your todo list" more than "doing the task".
I know I do. It's annoying to "carry" that todo item in my head all the time, with its danger of forgetting it, or the need to note it down somewhere, then remember to check the somewhere... So I know I'l feel liberated when I do it.
Yes, on the face of it this applies much better to "pay that bill" than to "write a book". But you'd be surprised. Soon you won't think of yourself as a procrastinator, you'll feel like someone who takes charge and does stuff. You know what people like that do, apart from the small stuff? The big stuff.
Good luck!