No, honestly, it makes as little sense as possible. Have you seen these things? They are as tall as you are, and you can't keep the arrow ready for more than a few seconds - maybe fifteen, if you are profoundly trained. And the gals' bows are probably scaled for their strength. Even if the combat bow is not a longbow, it doesn't really change much.
Right, I hear you man – longbows are pretty hefty. But the way I think of reaction fire is that instead of doing your action actively, you stop (or walk/do stuff slower) and wait/give yourself more time to react. Consider this completely, utterly, totally fictitious situation that definitely never happened (
).
My archer gal with her brand new combat bow sees one of them pesky chupacabras in a distance. She could actively shoot, or – since we're doing reaction training here (d'uh) – she could just stand her ground and shoot the sorry bugger when it decides to move. Just like her pistol-equipped gal pals. The chupacabra smells some tasty uber blood, shrieks in glee and starts running like a mother***** on steroids right at me gal. But no worries, Cap'n, she's no swabbie, she'll put and end to it soon enough! But what is this, suddenly my gal is overpowered by the weight of the bow – look at the size of that thing! She puts all her might to lifting and drawing the bow, but to no avail, and as in her last act of pure desperation she tries to pick up an arrow with which to stab the raving little imp, the hell-spawn pounces ravenously at her, fangs and talons gleaming in anticipation. "Goodness me, how many time units do these creatures have?!", I think in horror as my gal is unceremoniously ripped to little pieces of mutant meat in front of all the useless swabbies that are in panic shooting at the foliage and each others' backs. And then it dawns on me: if only she had taken a slightly smaller bow with her!
Hunting bows on the other hand are considerable weaker. While reaction firing from them is still a bit of a stretch, it is justified by game balance and not really that absurd.
So yeah, absurd or not, it would at least be nice to have some kind of warning on this in the bootypedia. I'm with you on the balance issue, though. It's also a nice trade-off between a more powerful weapon to use from a distance and a smaller, more portable, reaction-fire-capable weapon.
TL;DR OK no bug then!