Yes - in fact I would consider it a reqired feature on any quality hand sewn eight yard knife pleated tank. It really is a necessary step to reduce the bulk of all those pleats and make the kilt a bit cooler to wear. One word of caution - once the fabric is removed additional stabilizing steps are necessary to keep the pleats hanging right - so its not as simple as "just" removing the excess fabric. You are correct - its ALL in Barb's book.

This step is almost always skipped on a knife pleated five yard machine sewn kilt - unless you are sewing it yourself.

To be honest, I don't know about box pleated kilts - but I suspect this step is not required since they are generally about four yarders.