Britons: How do you pronounce 'inch' and 'lunch'?

I've found the answer. I've listened to the audio supplement of the book; the ʃ-less pronunciations are what Roach himself uses and that is how he speaks on the teaching material. Obviously, he wanted the audio and the written transcriptions to correspond fully, and he didn't want to give two seperate transcriptions for the same word.

Sorry, not ʃ-less, t-less.

There is a contrast between /lʃ/ and /ltʃ/. Welsh and belch don't rhyme. However there is no contrast between /nʃ/ and /ntʃ/.