Make things as simple as possible, but not simpler.
I tried to understand what Mark Foster had wanted to achieve with his systems and found out that his intention was to break one of the fundamental rules cited often by David Allen:
Originally Posted by cwoodgold
"Make things as simple as possible, but not simpler." - Albert Einstein
(it is a simpified paraphrase of the actual quote "It can scarcely be denied that the supreme goal of all theory is to make the irreducible basic elements as simple and as few as possible without having to surrender the adequate representation of a single datum of experience.")
Mark Foster's systems rely on constant browsing one long todo list containing all your commitments.