Very nice. I’m sure that is going to come in very handy.

Re. “Using formatted cell values for currencies, dates and more”. You can use SpreadsheetApp.getDisplayValues() to avoid having to go into the Advanced service.

I spent many an hour formatting the values before I discovered that function – although I didn’t know you could do it with the Advanced service too.

Another thing I’ve come up against was missed case-differences in the placeholders, so you can use (i) to make them case-insensitive (

This is my take on the popular mail merge everyone should have in their store cupboard: