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Maybe ... I haven't tried this particular plot branch for a while.
The tutorial is brilliant for this. What is the root of the problem? Crouching? That can be set to toggle, rather than holding the (Shift by default) key down for the duration.
The first level, at the Statue, is also pretty good for stealth practice.
Weapon choice might be a factor, too: it's a bit hard to hide if you shoot off the GEP gun ... :D