Depending on your situation is convenient the use or not of adrenaline. I wanted to comment about some Tips for Adrenaline use:
1) You
don't want to
store your adrenaline all the time,
USE it when you reach it, but use it wisely in accordance to your situation.
2) When you are in a very small map with lots of players is convenient to use it ASAP because there is very high possibility of encountering situation where you may shoot (unintentionally) your team mates. This makes your adrenaline to be reduced and you can't claim your combos.
3) Do not use your adrenaline when there is only 1 or 2 foes alive and most your teammates are alive. Chances are the round will be over very soon.
4) If you want to use the booster , use it on the beginning of a round, you are assuring that you'll get more health. You can even activate it before the countdown is over. You must use Booster when you are left alive and there are only 1 or 2 alive in your team. Make sure you have enough time to fill your health, it gives more chances for you to survive, and you will thaw faster if you have more health points (hp) with you. Do not use it in combat, it does not fill your health fast enough to give you an advantage.
5) Speed combo is very useful in some cases. When you are alive left alone in your team, but confronted to a couple of enemies and you need to escape fast. Speed combo allows you to thaw two times faster, use this ability to thaw your mates, never standing still but circling around them. Also, if you are a melee player, speed combo gives you a huge advantage to kill, the trick is not to return back but to keep moving in your direction... Is mainly run towards the enemy dodge fw and hit, (kill immediatly with nano) and keep moving. If you didn't kill don't stop and come back... circle around and pass through again... It gives you more speed while you don't change your flow direction. You can use the sprint too...
6) Pint sized (same combination of invisible) I personally don't use it often, not so much to comment besides it seems quite useful in close combat situations. Nevertheless it is not a high advantage when the enemies use explosive weapons, M50 grenade, Bort... etc.
7) Berserk is incredible when the correct combinations of weapons and situation comes together. First, use it when you know the location of your enemy and you are sure you are running towards an encounter. Use it with the correct weapon, this is at best with some energy, assault and shotguns that have good aim. The viper is deadly in this combination, also LS14, subassault, M46, M50, cylo AS , and shotguns sk410, mrs138... Don't use 59, xms10,.. and others that loose aim... you will shoot too fast and not hit anything. Use the iron sights!!!! Healing weapons heal faster than with the speed combo. So to thaw and kill groups is better to use berserk than run with speed. Be careful that your mates don't get in your line of fire or you'll be dead faster this way. And KS weapons... well you can imagine the damage you can do....
Enjoy your adrenaline
Maybe you are not trolling, maybe you are just trying to be fun, me is just too bad to anderstand eat 
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