It is still an effective way to work out buy/sell volumes before market opens and which way it would swing. If it was a rubbish tool, they wouldn't have been used/provided in all trading platforms.. for years, decades. Conditional orders (take profits or stop loss) of course would not appear here but normally are far away from current prices. buy volume > sell volume = bullish signal can't generally be argued with, simple is that. No further comments here.
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