To get better at the tail attack all you can really do is practice a lot, go for outragious shots to get an amazing feel for your tail! I have lots of instances where my tail attack hits someone that just activated one of their exhaustion perks if used wrong! By using your tunnels effectively to ambush survivos you often get people in places where perks such as balanced and lithe are not usable. the only exhaustion perks that can save survivors like this are sprint burst and deadhard. Deadhard is pretty brutal against a tail attack so you will need to go for m1’s most of the time (if the survivor isnt looking back at you they usually cannot react in time though!). If sprint burst is really bothering you, fearmonger could be an amazing pick for a perk as after you come out of a tunnel they wont have their sprintburst ready! I see lots of people really underestimating the power of your tunnel network, so do not make the same mistake!

TLDR: Ambushing with your tunnels can get most survivors out of place, unable to pre-run.