This was actually normal back a few versions ago up until it was removed for some reason that I have no idea. I wouldn't really support this suggestion at all mainly because if you're out, you've got one shot at getting out. Can't just spam away at a supples crate while you're hiding in a corner.
Focusing on the 'luck' part here; Escaping as a D-Class is supposed to be lucky. Guards are already brain dead and would probably accidentally release you and Researchers (Mainly junior's) have the chance to actually say 'fuck it' and attempt to leave with a D-Class even if they're a CI or not. Though in general, the main objective of a D-Class is not to escape.
I don't really see anything wrong with this, as it's probably better for a high risk/ high reward like you've stated.
As pointed out, this isn't a game bug, it's a game feature. I'll have to dig around and see why it was changed like that. In addition, we shouldn't be giving D-Class incentives to escape in any form. They already have enough incentive in the first place.
For these parts, Part A is useless improvment because the guards will shoot D-Classes when they utter a single microagression and for Part B, pretty sure this is already a rule. Will have to check on it.
All in all, I will -1 this because D-Classes shouldn't be given a leg up because of their status. They're supposed to be tested on, not given the opportunity to escape with better luck.