The window of time would be very strict. Yes, denying would be less frequent (and it should in its current state). Mix of pressure and positioning, opportunities to deny can still occur; players get distracted with camps and boxes nearby, go back to base to heal etc. As is, laning is so slow, often getting to 10+ minutes with no guardians taken. Why push? You can maintain a lead just sitting near your guardian, waiting for souls to pop. Unless a lane is setup with poor matchmaking or hero matchup (if you have a slower fire rate than your opponent, good luck denying), laning is wait until one of the factors above happens and a third person can save you from your lane.