It's possible - I don't really have any mounts going so can't confirm.
"/f" -- forces the software scan.
"/f-" -- forces NOT to run the software scan.
I *THINK* the idea was that we don't dive down automounts by default ('cos there's some folks who have terra and peta-byte sized storage volumes attached, which is "fun" as you can imagine) ... but you may want to confirm this through support. Which leads me to the next part - what you say makes a lot of sense (if LDISCAN doesn't take note of any "true/false" values for "-x") - that'd definitely be a defect, which you should log with support.
They should be able to get back to you about the default behaviour (which I am really having a moment of self-doubt about whether this is just something I'd discussed or whether this was indeed de facto truth).
Part of me also wonders ('cos we have folks who don't "behave nicely") that we can't automatically assume that "/net" is indeed what it ought to be ... I'm sure I've seen stranger things . (Such as production app being installed under "/tmp" for historical reasons that brought up great desire to faceplant ) -- short of it is, we can't "assume" (sadly) that things are what they ought to be, sadly .
Hope this helps.
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Addendum - yes, by default, LDISCAN should not dive down network mounts, as "-x" enables it ... so if that's not the case, report it as a defect to support please. A simple "./ldiscan -h" confirmed expected behaviour
