You don't say if you are using Themes or not...
I don't notice descrepancies between layout and browse.
Themes are generated and managed by CSS and some of the base-stylesheets have margins and borders built in that you cannot control (in standard installs). It may be you are experiencing the effect of using one of these.
... just guessing, mind you.
Thanks for responding. I think you're at least partly correct but it was mostly 'operator error'.
I had turned of the auto-sizing on all fields because I was getting some odd effects from the default settings. It turns out that once they are off the odd effects get worse! Anyway, I reinstated the appropriate settings and everything is fine. (I'm still a little confused by how auto-sizing of fields affects layout parts?)
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