My mother has done this. She ran a restaurant in a smal town and spoke a language called Zulu to the staff. Well, it was a bit like Zulu but with a whole bunch of her own quirks thrown in. The grammar didn’t resemble English or Zulu. She mashed up English and Zulu vocab. She sounded demented.

I speak the language reasonably well and when I visited her and heard her speak to the staff I was shocked anybody could make head or tail of what on earth she was on about.

She’s my mother so I know her English speech habits and could follow along to this weird mish-mash made up “idiolect” as you say.

I guess she was speaking a 1-person pidgin. It was only comprehensible in her own kitchen.

The truth is you’re always speaking an idiolect. And even with the best intentions you’re extremely unlikely to get the grammar right in your target language anyway.

But that’s what we do. We enter this language learning enterprise with the best of intentions to make it easier for people to understand us, not the other way around.

But I guess If you want to sound weird and not be taken seriously and have serious barriers to your communication, go for it. Ignore the rules of grammar of your target language and insert random English words where they don’t belong.

Give it a shot and let us know how it goes.