Both tactics (being the same for both classes) are useless in a manner that whenever it pops the player ends up being (in most cases) free renown for the enemy ressurecting with very low health pool and dealing low amount of damage. Also the player would have to slot it in place of much stronger tactics, therefore nobody is using it.
Solution
There are few solutions for this tactics to work without being overly powered in the process (the first one being my favourite)
1. Give the player an option to ressurect where he died or release at the spawn point (warcamp, scenario respawn spot) with 10 second to chose an option (similair as when player get ressurection from healer). This would allow the slayer/choppa to decide if he wants to join the fray if he see that the fight is still going on or release at a safe spot without feeding the opposing side with renown. 10 seconds window to decide would stop the player from exploiting it's use with backdoor tactics spawning behind enemy lines and would be enough to make a decision how to respond to the situation on the battlefield. Keep the damage and low health pool as it is in original state.
2. Ressurect the player immidiately with bigger health pool: 50% at least (75% could be too much, up to discussion), even with this solution the player would be an easy target and potential free renown but at least it would give enough time for healers to react and heal him up. Edit: optional, giving player the choice of ressing or not as it was brought in discussion by several players
3. Ressurect the player immidiately with the low health pool (25% as original) but boost the damage done upon getting up. It does 250damage according to carreer builder, if it would deal twice that damage (which of course would scale with points invested in the according mastery tree) it would be a nice damage dealer which could potentially put pressure on the closest enemies.
4. If the solution no. 3. seems too powerful (damage done upon getting up could be scaled up to over 1k damage aoe, needs some testing tho) the increase of damage could be done not to all of the enemies in the 40 yard range but only to the 3 closest ones.
[Lore input

We need to remember that this tactic is high up in the mastery tree (12 points needed to unlock).
Another thing is the chance of getting up, 100% chance would be too powerful but I believe 50% chance would be enough for a tactic that is so high in the mastery. Utilizing this tactic can prove useful for slayers/choppas that want to rely more on a survivability rather than pure damage output, at R40RR40 one can go and stray from the usual 'go-to' builds (in case of a slayer ID+SL+HealDebuff) and merge it with another builds like Rune of Absorbtion/Furious Choppin'