Kilt hygiene:

HOT BUTTon issue.

As a daily kilt wearer, the "soil" that I encounter is more from the seats on the train or bus, along with the grit in the air of the city. The occasional beverage spilled in the crowds at pubs and concerts require quicker cleaning.
I shower every morning, and know that what is inside the kilt is quite clean. This is with the kilts (34) that I own. Whether a kilt hire or any other kit hire, there is a layer between me and the hire kit. This is usually a very long T-shirt that is available at almost every store that sells "urban wear" for men. The T-shirts that many of our urban youth wear over themselves usually hang to mid thigh - knee area. This covers the area that is occasionally displaying their boxer shorts when the shirt rides up or they are wearing a regular length shirt.

The next area is modesty:

I have found briefs that are a beige colour, that is close to my skin tone. These are worn on the days that I teach very small children, or could be involved in a wardrobe malfunction. As these tend to result in my sporran being pushed out a bit, I only use as necessary.

I have never worn anything inside my trousers in my life. Though the trouser wearing is limited. Again if hired kit is involved, I prefer to have a layer added, be it boxers, boxer briefs or briefs as I do not desire to pick up any free gifts that might come with the hire kit.

There is also a layer between me and the kit that belongs to the band that I currently perform with. it is only for our mutual protection as some pieces are "shared".

Many who wear trousers, prefer to be regimental at all times. The same applies to wearing any other kit, kilts included.

Fortunately the interview with Brian Wilton was far more accurate than the newspaper article. (Boston Globe page 3 today.)

The soiling that has occurred to hire kilts in the U.K. as reported in some news articles would probably not be hindered by the wearing of pants under the kilt as the volume would result in two soiled garments, at least.

My tuppence. Your results might differ.

Slainte