Want less emphasis on speed? Let tick marks be less than $0.01. Market-makers are clearly willing to provide spreads of less than $0.01. Any time the price of s

Want less emphasis on speed? Let tick marks be less than $0.01. Market-makers are clearly willing to provide spreads of less than $0.01. Any time the price of something is artificially moved out of market equilibrium, there will be queueing (either to buy or sell the good). In this case, there is queuing to provide liquidity, and market-makers have every incentive to try and jump the queue. Instead of competing on price (they can't), they compete on speed.