[jaen]

That's just making things harder to write by disabling useful features.

Always using `select`s can actually be MORE inefficient than using predictable branches, as for a select both sides of the conditional must be evaluated, while for non-divergent "warps", masking+branching skips the instructions entirely.

It's not hard to learn that `if` has a performance cost depending on its divergence (every GPU programmer already knows that) - sure, it's harder to quantify, but it can be strictly better than select, so this is actually inviting inefficiency in certain workloads.

[goosethe]

this is largely true. By making the cost explicit I get to publicly thrash the programmer that tries to do what you propose.