So when WWE rehashes Vince McMahon vs Bret Hart what does that fall under? But but that is different somehow you say. These excuses get old. Just admit they do it and criticizing TNA specifically for that is hypocritical.
TNA has several re-imagined guys themselves. However, show me where TNA has copied an active wrestler's gimmick from WWE. I do not see it. While WWE has been guilty of the flip side on several occasions.
The only real case of WWE copying a TNA gimmick I can think of is TBP and, the thing is, TNA can't really copy an active wrestler's gimmick as TNA is a lot smaller then WWE and copying a gimmick would only re-enforce that image. With WWE they can do it to TNA because, sadly, TNA is still only a small, relatively unknown name in mainstream wrestling so, to the majority of WWE fans, the gimmick is new. Then if they catch sight of TNA they'll automatically jump on the "they copied WWE" bandwagon. It's a vicious cycle (as ECW found out when wwf took their hardcore style and made it appear they were original with it) but them's the breaks.
My problem with TNA is, as I've said elsewhere, not the talent or such. It's that they have the potential to be great as all the pieces of the jigsaw are there, they just seem to be being put into places that WWE would put them, instead of TNA making it's own way.