It helps to think of the depth table as a game for some,...

It helps to think of the depth table as a game for some, psychology for others, and a statistic for everyone - ease of access, a lack of trade limits and no minimum position size or price makes this possible for those with access (no I'm not one).

So this is free and easy direct market access. Commsec for example won't allow you to do this due to limits on size and price.

Day traders / short termers analyse the buy and sell tables - not just the current bid/ask spread. I tried it for a while using a simple spreadsheet to retrieve the depth table every few minutes, then look at possible trends. For anything longer than a few days entry, was a waste of time unless you are looking for small fractional gains.

VWAP on the bid side top 5, top 10 etc likewise for the ask - and movements in volumes and VWAP spreads looking for patterns of strength or weakness. One would be a delta across the highest to lowest prices etc. No doubt this happens in any market where anyone can access the market depth. Algo's/BOTs scan for them and are integral to an automated trading program.

Some place small orders at buy/sell levels to keep the price flow contiguous not to leave gaps. This guy is playing with the depth spread and means positively nothing to anyone else.

He/she is what you talk about when there is nothing to talk about. Until this garbage gets properly regulated with the rest of the algo/bot rubbish and market access is made consistent for all, then consider it a sign of the times.

(this can happen anywhere).

rgds,
pw