I was pondering something very similar to this about 10 minutes before he talked about it only I was thinking about changing perspective for the given task, that is: "what 'mode' do I have to be in to get this done?" in place of 'Y'. His short sentence is much more elegant than what I was trying to think but I think 'mode' also fits just as well.
Basically, I think we get too overwhelmed (emotion) with what we have to do and breaking it down into smaller chucks may not be enough. Breaking it down into modes or specialties might make it less daunting. We can all 'plan', 'study', 'code' or whatever hat you need to wear along the way and wearing them all at once, even on a small task can still be overwhelming.
For example, say I have a new coding project but I'm having trouble organising it into chunks as I'm new to the platform/API. What I can do is say "ok, I need to put my 'study' hat on and learn just an overview of how this all works" (study mode) then go back into 'plan' mode to reorganize tasks into further modes to complete item one ('hello world' app say), rinse and repeat.
Your "study hat" is just that - you get familiar with the complex underlying mechanism and then much of the resistance disappears.
Get familiar, get started.
But learning how to break things down into chunks and make a checklist makes it a lot easier to avoid that. A well defined task is actually fun to do, and I'm much less likely to avoid it.
In knowledge work, we need to:
1. Define the work
2. Do the work
Can't do what's not defined.
In general, the simple advice I give our clients is to take a piece of paper and a pen, and put all the ideas about the task out there. Take 5-15 minutes and try to define it.
Basecamp's Shape Up book is a lot about managing the unknowns.
"In situation X I will do behavior Y to achieve subgoal Z"
His example was
"When this workshop ends today, I'm going straight to the library to read 4 pages of that paper that I'm struggling to read to achieve the subgoal of finishing this paragraph in my thesis"
The idea is you don't have to think about some vague topic. You just go on autopilot like, oh the workshop is over now I have to do this thing, therefore you're more likely to do it.