In releation to sending traffic to toplists, the vast majority that I have dealt with don't really give a brass razoo, how you send to them.
The basic most used requirment is that the site/traffic you are sending is the specific niche, ie: they get the shits up when you send teen to a gay fisting toplist.
And as for the linking most again don't care so long as they can see the recip link back to them, (which you use natuarly to send the traffic to them) Be it off your main page or catagory pages.
I've sent it to them by skim, trade, blind click and all have been fine for me. The only thing I can think of, is that blind click sent, would be a pox prod% / return, rather then a link that says "click here for more 'niche' sites"
-N