If you have had several fish die in the last few weeks the LAST thing you should be adding is a new tang.
Figure out why you lost those fish first.
Is your tank young?
That is first and foremost on the list of things to do
IMO, you can have a tang for a short while, but it SHOULD outgrow that tank. IMO a Kole would be the best choice of all.
As for the "no never" and "yes everyone does it" arguments, neither help very much.
The strict tang police annoy me frequently, and the "its not the ocean anyway" argument is equally frustrating...when you keep animals for your entertainment you have a responsibility to provide a minimum amount of care regardless....and here we have a poster who wanted some real insight, so far as I can tell.
Puffer - I definitely commend you for your question and understanding that you might not have a tank suitable for these fish. I think that so long as you understand that a yellow tang will not be suitable long term, and that you WILL need to find it a new home (sounds like you already have one) then I don't particularly have an issue with this so long as the tank is not heavily stocked.