Workarounds

I'm going to recommend AutoHotkey yet again - you could rig Fitaly slides that will type sequences, or even exclusive keys, that will cause AutoHotkey to generate the expanded responses that you want, along with commands that will vary AutoHotkey's behaviour. A graphical state indicator to go with that might be do-able - paint a different colour title bar for Fitaly, perhaps. Emmanuel would not be involved ;-) AutoHotkey also probably can spot which application context is active, and provide different expansions accordingly.

Then again, the matter of medical terminology has been addressed several times over, including by Textware in Instant Text, I think.

For "risky" slides, I have set a longer slide length by making the short slide the same as the key without slide. For a similar effect on longer strokes with multiple functions, you could set a medium length stroke that doesn't do anything, and then the longest stroke in the same direction performs the function. If you mis-stroke in that case, you only hit a dead zone that does nothing.