Every productivity method promises the same thing: a trusted place for stray thoughts so the current task survives. Most fail not because the tool is wrong but because the capture step costs more than the thought itself.
The fix is to make capture one action, always in the same place, reviewed on a schedule you actually keep. Paper works. A single note file works. Eleven synchronized inboxes do not.
Measure the system by one number: how many captured items resurface at review. If the answer is "all of them", the system is working regardless of what it looks like.