What addins do you have running? This would be the first place to look.

If you open Word while holding down the Ctrl Key (and elect to open in Safe Mode) do you see the same lagging behaviour? If not, then it is definitely an addin or template causing the problem.

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Andrew Lockton
Chrysalis Design, Melbourne Australia

And if yes? I now strongly suspect that the problem has to do with some style changes I that I saved not "only in this document" but rather "new documents based on this template". However, older docx that I have on file, written by someone else, also exhibit this behavior.