Your lawn may seem perfect, but it still has a MAJOR problem. Its the same problem that every other lawn in DFW has, whether they are perfect or not.
The problem is the hundreds and hundreds of seeds that are sitting in your lawn, waiting to germinate and grow into nasty, ugly weeds. Every lawn has them, there is no way around it.
Weed control is all about keeping weeds from coming up in the first place with a pre-emergent. Whether you have weeds in your lawn right now or not...there will be a LOT more coming your way if you don't take action and get a spring pre-emergent put down ASAP!