Infinitive in pluperfect/perfect conditional construction

[signormalatesta]

My Dutch teacher and I are reading a short story by Guy de Maupassant translated from French into Dutch at the moment. We read this sentence the other day:

Maar dat lag natuurlijk aan het feit dat hij diplomaat was, en zonder twijfel heel wat dames had helpen uit- en aankleden.

This caused no trouble for my native-language Dutch teacher but did for me. The translation of the sentence seems to be:

But that was naturally due to the fact that he was a diplomat, and doubtless had helped many women to get undressed and dressed.

My question is why this was not presented as a pluperfect in the Dutch, such as:

...en zonder twijfel heel wat dames geholpen had uit- en aantekleden.

as it seems to be in the English, or even as a perfect conditional, such as:

...en zonder twijfel heel wat dames geholpen zou hebben uit- en aantekleden.

i.e what is the function of the infinitive in the source sentence? I can find nothing about this in any grammar I own.

Thanks!

[Bieneke]

My question is why this was not presented as a pluperfect in the Dutch, such as:

It was in fact a pluperfect, but a disguised one.

You probably expected: "... had geholpen uit- en aankleden." In Dutch, we have this grammar rule: "When a past participle serves as an auxiliary verb, it turns into an infinitive." The past participle 'geholpen' serves as the auxiliary verb for 'uitkleden' and 'aankleden'. Following the grammar rule that an auxiliary past participle should turn into an infinitive, we use 'helpen'.

See also: http://www.dutchgrammar.com/en/?n=Verbs.Au05

[signormalatesta]

Brilliant! Thanks so much!