That is most likely right but I don't know that anyone has actually tried it even to this day to be sure. Year's ago there was a case where a caramel line was known to throw albinos from time to time and some hets from that line failed to produce caramels and only produced albinos. It got me wondering if albino and caramel might be alleles (different mutations of the same gene) and actually compatible, maybe producing a caramel looking animal. But with the general assumption that they aren't compatible and that the double homozygous albino caramel would look albino and be a waste of the caramel gene I don't think many if any would be willing to try. I bred a possible het caramel to a possible het albino years ago but only got normals and haven't proven either parent yet.
I have heard a rumor that a double homozygous albino x caramel albino burm has been produced. I was told that it was visually different from the albino and the caramel.
Interesting. I hadn't been keeping up with burm mutations to even know there was a caramel. With ball python mutations becoming less expensive someone will surely eventually try that combo. I had planned to do it if I ever get both homozygous animals (I don’t have either yet) but with the kinking in caramels and a new and improved caramel like mutation starting to be available wasn’t sure I still wanted to work toward having caramels anymore.