Actually the word 'trading surge' should not be construed with what I sometimes use 'surge' or 'volume surge'
A Last Sale Screen may have buys coming in every 20 seconds, or every 10 seconds or once a minute.... you get the picture.
In other words it's a steady flow, tick tick tick.
Another way of putting it. Your sitting down and your heart rate is a steady 60bpm. Your fast pace walk is a steady 85bpm, and so on.
A trading surge is a faster pace of buys/sells with little change in the PPS. Not sure if that's correct terminology, haven't checked. And really to me it doesn't matter because understanding the performance of an L2 & Last Sale Screen [together as it happens in real time] and [separate as it happens in real time] with the same stock IS... multifaceted.
Reading both L2 & LS screens during a run could bring a combination of maybe 50 different scenario's, not sure, and believe too it could never be put down on paper.
I have yet to think of a great analogy!
Maybe trigonometry which is supported by the theory of quadratic extensions, ever changing... so that in L2/LS reading new formula's built in the middle of a finite set of values as it happens.
I also think intuition plays a part of this during each individual process, based on past experiences.
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