Still there's a difference between not doing the maximum possible to prevent theoretical exploits (like caches thing) and adding an externally controlled featur

Still there's a difference between not doing the maximum possible to prevent theoretical exploits (like caches thing) and adding an externally controlled feature that crosses into SUID territory and begs to be exploited. It's like the difference between not buying the door made of strongest alloy steel and just leaving the key under the potted plant. The latter makes you say "what were you thinking?"