It will probably jam the scanner and could damage the feeder. Remove the staple and scan the two pieces separately. If you need them scanned on one page, use scotch tape, or scan them on a flatbed scanner. Your user manual says "do not scan wet docum...
I like this one from Fujitsu:
A buyer generally looks for a ppm(pages per minute) speed of the scanner,B&w and colour..plus whether a scanner scans in duplex(both side) or simplex(single side)..the format which we get after scanning eg. a pdf file a OCRed file,a word file or jpg....