A hypothetical breeding question

[Lord Sorril]

Breeding a possible het x possible het is a losing proposition unless absolutely necessary. Because the majority of the matings are either het x normal or normal x normal.

Yep! You have good math.

The X factor is that *some* (not all) recessive genes in the Het form are capable of leaving clues that can be observed by a keeper familiar with that genetic line (aka distorted patterns/lightened coloration/oversaturation of pigment/ringers).
If the snake has zero deviations-then you are stuck relying on genetic odds...which I think would be awful and probably not worth the time/effort to proof breed...