Inviting people is less harmfull then kicking people.
If someone gets into the clan system, whom a higher ranking member doesn't want there, he can be kicked.
Getting a discouraged member back can be more tricky.
and while we are at it
Rank 6: set rank 1-5 (an officer organising the teams)
Rank 7: set rank 1-6, accept new members
Rank 8: set rank 1-7, accept new members, kick member(with rank 1-7)
Rank 9: set rank 1-8, accept new members, kick members(with rank 1-8), manage armory, manage bankpayout
Rank 10: can do it all
perhaps there is a in detail description what each rank can do? I suppose there is implied information which didn't fit into the pulldown menus. If not i would be happy to collect that data and write a short faq.