From the book "How Plays Work by David Edgar, near the end of the preface, he writes of Friedrick Schiller, back in 1788, writing to a friend about what we might call the 'right vs left' discontinuation:
The ground for your complaint seems to me to lie in the constraint imposed by your reason upon your imagination… It seems a bad thing and detrimental to the creative work of the mind if Reason makes too close an examination of the ideas as they come pouring in – at the very gateway, as it were. Looked at in isolation, a thought may seem very trivial or very fantastic; but it may be made important by another thought that comes after it, and, in conjunction with other thoughts that may seem equally absurd, it may turn out to form a most effective link. Reason cannot form any opinion upon all this unless it retains the thought long enough to look at it in connection with the others. On the other hand, where there is a creative mind, Reason – so it seems to me – relaxes its watch upon the gates, and the ideas rush in pell-mell, and only then does it look them through and examine them in a mass… You complain of your unfruitfulness because you reject too soon and discriminate too severely.
That quote is attributed, in the footnotes, to -- Philip Rieff, Freud: The Mind of the Moralist, Chicago: University of Chicago Press, 1979, pp. 88-9
In a nutshell, I think that this is something to which I have been guilty more frequently than not: throwing away ideas as they transpire, rather than letting them percolate and intertwine with subsequent ideas and thoughts.