@monkeyjoe
<b>> The only reason I was looking at the actual short-term PNL as an indicator is because of the high volume of trades</b>
"high volume" is a relative concept. "high volume" respect to what ? It does not seem "high volume" to me. Actually the trading pace in this current session feels quite calm.
Anyway, the <b>trading frequency</b> could be increased by reducing the entry spacing and making less stringent the entry conditions. My personal believe about this, is that there is a limit to to how "fine" and frequent you can get (well, in any case certainly you can't get too close the spread), because there seems to be anyway a lower bound beyond which the MM algos will easily massacre you, if you try.
What seems to happen is that, most often, if you try, some MM algorithms will start rapidly "fluctuate" against all your frequent orders and make your local loss grow beyond any limit (this will be hard to "undo", as you will soon have too big sizes standing on the wrong side of the mkt to be recovered).
I have seen some instance of that with some instruments, even if not in the same measure. [The most "aggressive" case I have seen I believe to be UGAZ, which seems equipped with an highly aggressive logic (just my practical, personal experience however, I have no other "proofs") ]. In this sense, somehow the mkt seems to be organized in such a way as not to allow any <b>"market taker"</b> to easily get away with quick and easy money (at least not on a systematic basis).
<b>>My understanding is that high frequency (HF) systems generally show you whether they are profitable or not much more rapidly</b>
Well they obviously do in relative terms. It depends on what is the logic by which you judge whether you are on the way of "profitability" or not. In our case we just want to see the "G-L" grow steadily and at the same time bound the "unrealized" in a finite range.
From my point if view, if I don't see a "sound reason" (that is, considered so by a reasonable number of reputable experienced people) why a trading methodology must be profitable there is no positive PNL equity curve long enough that will ever change my opinion that is a pure <b>work of chance</b>. And, on the other hand, you <b>will never have any other way to "prove" that is not</b>, if you do not have a sound reason to justify it.
This is similar to when people talk about "correlation" between phenomenons ("spurious correlation"). If 2 facts have no "logical dependence", whatever high is the absolute value of r (correl. coefficient) that you get, it will have no meaning. It's not the fact that you can compute something that creates a phenomenon. The correlation <b>must exists in the first place</b> (at an agreeable logic level), and then its measure can start making sense
<b>>some novel tradable feature of markets in how prices are revisited... perhaps a feature that is not adequately explained by a mean reversion parameter in a GBM model because of concepts like "support" and "resistance" used in technical analysis.</b>
Nope I have not. And I don't believe they exist at all

I look at all the above concepts as irrelevant to our purpose, attributing to them a purely "descriptive" meaning (which is a worthy role, anyway).
<b>> Specifically, what happens to Layer 1 if the price runs away?</b>
That depends on what you instruct the game to do. In my current example games, if there is one side running away, players from the opposite side will kick in (the "intensity" of the hedging action, order sizes, etc, is specified in the game rules.)
One important thing to note, is that in that post I have mentioned 2 layers just to make clearer the illustration. In reality, as I have also precised, <b>all the work is done on 1 (unique) layer and the players are, as we say, "superposed"</b>.
(The "layer overlay" can also be used, but it represents an higher level of logic overlying, say at a "macro" level.)
<b>> If Layer 1 must simply wait and endure the drawdown</b>
That is a matter of how you define the game. I currently tend to like to hedge promptly but gradually, even if that slows down the growth. The intensity of the hedging action may also depend on the nature of the instrument and on the side (buy/sell)
(eg, ultrashort can be treated asymmetrically: that's why I am calling the game I am using "bias").
<b>> It would be interesting to hear what sort of options/controls you have put in place for these types of scenarios, as any scalping strategy's profitability really depends on how runaways are handled</b>
Well, as we said before, this is really a "tug of war" between gain and loss growth rates. So the goal of creating good games is to realize a good balance, which provides some protection, which be comfortable to trade (and different people may have different "pain thresholds"), but at the same time does not make the growth too small, or even negative. Our edge is the fact we are "recycling losses" when possible.
Where "edge" here does not mean clearly we are guaranteed to become rich soon, but more reasonably that our architecture is providing a <b>statistical advantage</b> respect to a similar strategy that would not be using the past trading information and it's actively using that advantage to "unbalance" the natural 50/50 gain/loss ratio (normally obtained with the odinary "memoryless" stops) in our favor. You just establish a positive "drift", then time must develop it and gradually show it in the PNL (clearly, the larger the folio, also the slower could be the process). In this sense I humbly talk of <b>"strategic dominance".</b>
Sure, about games (entry rules, sizing, hedging intensity, etc), it's a completely open field of research and engaging exploration. And one might also tune them respect to entire "classes" of instruments", in order to adjust the game rules to the structural features of the instruments, eg. commodities, indexes, ushort ETFs, etc.