I am in the preliminary stages of planning a project with a client to redo their current website. I took a look at their current site to see what issues they are currently dealing with and upon inspection I noticed that every page is being rendered entirely using XSLT. I am familiar with XSLT, I have used it to render custom controls that need to be refreshed often on the client-side, but never to render an entire page.

Help me become less ignorant, what could be the reasoning behind this? What benefits or disadvantages does this bring to the table?

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