Do tails fill gaps?

[creppie]

I prefer a solid fill so there's no question about it. Some will argue to no end that a solid fill isn't required. Based on that point alone, I'm willing to accept that alot of traders will forego placing bids at the far end of tail-filled gaps. This would translate to less MM pressure in making a market at that pps and ultimately may render tails-do-fill-gaps argument true. Either way, trade happy! :)