The only drawback I see to this approach is that the page with the large images will take forever to load - especially if the first thumbnail a person clicks is the last image on it. Sort of defeats the purpose of having thumbnails in the first place 
Doing them on individual pages is not that slow. You just make one page with the layout you require for your image and save it as something like pictemplate.htm. Then each time you need a place to put the new large image you open this page, save it in the name of the new image and put in in your large image. Then right click the thumbnail and chose hyperlink and change it to the name of this page.
That is more or less what I did on this site - though I used pop ups for each page which, to make it fast to do means fiddling with the code. www.darlenegarr.com
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Katherine
InKK Design
LinKKs - Kilkenny's Online Magazine
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