[plt-scheme] append!?

Will Farr wrote:
> I think the subsequent posters may have overlooked this point: append
> *does not need to copy its last argument*.  A quick (inefficient)
> definition of append:
>   

You're right. I even did few tests and append! is only marginally faster.

>  So, you don't have to worry about
> using append with a long final argument; instead you should worry
> about using append with long first arguments :).
>   
The point is, in that case I should take care about last cons in the 
first list, right?