Email Link Performance Report will show you the following
Clicks = Total # of clicks on this link (Not unique clicks).
% Clicks = Total # of clicks on this link / Total # clicks of all links in the Email (not unique).
Leads = Total # of unique leads that clicked this link.
% Leads = Total # of unique leads that clicked this link / Total # of unique clicks by leads of all links in the Email.
Email Performance Report does reflects "unique" opens & clicks
(note: if you hover over the column it will tell you what it is):
Also keep in mind that in other Email reports to use the number of delivered when calculating the percentages.
A common misconception is that it is based on number of sent.