So a compression scheme that first shortened end tags, then applied a standard compression would be more efficient size-wise. If you are worried about file size, then compress your files. Tags, being short strings commonly used, compress really nicely with the common compression algorithms out there. The compressed files differed by only a few 100bytes from each other. The gains from short end-tags did not carry over into the compressed versions, and the compressed versions were so much smaller there seemed little contest.
Compression is a far better approach.
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