Then, BlackBandit, if you're SO clever, are you able to provide an explanation of how the use of "et al" is wrong rather than just a statement to that extent - and then nothing?
Otherwise, several definitions for you:-
Sisyphean definition
Sisy·phean (sis′ə fē
′ən)
adjective
- of or like Sisyphus
- endless and toilsome, useless, etc. a Sisyphean task
Sis⋅y⋅phe⋅an /ˌsɪs
əˈfi
ən/adj
1.of or pertaining to Sisyphus.
2.
endless and unavailing, as labor or a task.
Thus, my usage is correct, and more to the point, most apt.