Look if you want to play a pseudo tank you are better off going with a drg or monk. Drg has a 50% damage reduction for 10secs and a 12k life steal. Monk has 16k worth of shields in thunder clap and riddle of earth can heal you for 4k plus 50% of all damage taken over 10 secs. Sam has a 25% damage reduction for 5 secs and the damage buff only applies if they hit you and lasts 3 secs and your last skill on your combo does 100% of damage done as a life steal, which will not help you 9 times out of 10 if you are being focused in any meaningful way, maybe as a way to off set cleave damage at most.
If we still had the 50% chiten yeah maybe we could do it. But with such a nerf we either need to do more damage or get rid of casts for the skills since they don't hit hard enough to warrant a cast time on a melee job (mind you sam cast times are only 0.14 secs faster then a black mage cast)
And yes I have taken Sam to crystal every season including this one, I prefer sam since I play it in pve as well but the other jobs are just better in every way and I can play them just as well.
If sure 50% is a bit much I kinda just was thinking about Fire Resonance when i wrote the original post thats pretty much it.