Can I stack shield recharge delay bonuses?

My commando currently has 5 points in Willing for -60% recharge delay, and I've also got a Tactician class mod, which gives -26% recharge delay to my team.

Do skill bonuses stack/combine in any way with class mod bonuses? If they do, is there a limit?

They do stack for sure :) However having -100% recharge delay doesn't mean your shield will start charging instantly. It will take half the time to start charging.

Here is another post, somewhat related: How do extremely low accuracy levels work?

Shield recharge delays stack multiplicitivly. So if you have willing and a class mod you can get your shield recharge delay by taking the delay listed x.4 x.74 By the end of the game you’ll have multiple buffs for multiple stats so of course it bloody stacks, but you can’t just get pressure and willing and have a bee that works while on fire. If you want 0 delay you need one buff of 100%. But if you just want a really small delay, stacking buffs works great.