Art. 282 lid 4 Rv, familiezaken

[cricketfan]

Hello forum members,
I hope you will excuse me writing in English. I study the Dutch case law very closely.
I am interested to know what your experience is with the application of Art. 282 lid 4 Rv in family court cases in The Netherlands.

The first part of the Article states "Het verweerschrift mag een zelfstandig verzoek bevatten, mits dit betrekking heeft op het onderwerp van het oorspronkelijke verzoek."

How strictly is this applied in practice? For example, if the original request was, say, a reduction in kinderalimentatie, or a request for a change to 'zorg en opvoedingstaken', and then the verweerschrift contains a radically different request, such as "vervangend toestemming voor verhuizing naar het buitenland", what is the typical practice of judges in this country?
My impression is that such a zelfstandig verzoek should be prima facie niet ontvankelijk.

And what about the second part of the Article?
It states "De rechter kan aan de verzoeker en aan de overige belanghebbenden gelegenheid geven tegen dit zelfstandige verzoek een verweerschrift in te dienen".
Why "De rechter kan" and not "De rechter moet" or "De rechter zal"?
Does this mean that the judge has complete discretion as to whether or not to allow the person who originally filed the case to file a defence against the counter-claims? Can the judge simply decide not to allow a defence against the 'zelfstandig verzoek' to be filed without giving reasons, and then make a final decision taking into account the zelfstandig verzoek, with no rebuttal thereof on file?

If the courts are lenient on the first issue and fuzzy on the second issue, does this effectively mean that bad faith parties/their counsel can completely derail/hijack a case at will by late filing an unrelated zelfstandig verzoek, and get away with it?

[bona fides]