Quote from Lawrence Chan:
Volume (better way to say this is Size) from a single order cannot move the market.
At best a large order can hold the mkt at a particular price level.
It is the number of trades that follow thru in a particular direction that matters. Of course, if among those trades you see some reasonably "sized" orders, that makes the move more believable.
Thus tick charts do have their position in technical analysis, especially in intraday trading, because they reflect the level of participation among the traders.