Someone told me Tucker had some arrangements of his own not in the TubaChristmas book, not the Alec Wilder nor the Norlan Bewley charts. Maybe they’re mistaken and I was misinformed.
It’s all tuba and euphonium, it’s all good. 
In my lifetime I’ve played probably close to 50 TubaChristmases at various locations, mostly up and down the eastern seaboard; I used to do three or four a year, including the big one in NYC. Would love to do that some more, perhaps in times to come.
Playing the piccolo part to “Stars and Stripes Forever” on the tuba is an old trick that originated back when Professor Bill Bell played with the Sousa Band, I do believe. (Bit of music trivia: The piccolo player in the Sousa Band during Bill Bell’s tenure: the young Meredith Wilson, who would go on to write “The Music Man” and other things. Bill and Meredith Wilson were the two youngest people in the band and hung out together and were good friends so Meredith didn’t mind losing the solo, I guess.)
I’ve played the piccolo part, taught it to other tuba players in the line, and think it’s a cool thing to do. Not meant to offend any piccolo people out there. Also played “Bugler’s Holiday” with other tuba players just for fun. You can play anything on the tuba you have a mind to.
(Don’t ask me for “Flight of the Bumblebee.” Still working on that.)