It would lower the proc chance from 72% to 41% (on Defender), and make it less consistent. The end result would be about the same DPS if you use it when it's up, but less reliability. To explain my reasoning:
Bomb can fit 3 damage procs, a -res proc and an FF proc. Let's also say the power's damage is increased by 100% with buffs and a damage IO.
And on a high recharge build, 30s is reduced down to around 7.5s while 16s is reduced to around 4s. Add the 3.3s cast time and you have:
For 30s recharge:
36.15 * 2 + 71.75 * 3 * 0.72 = 227.28 damage, more reliable
7.5 + 3.3s = 10.8
227.28 / 10.8 = 21.04 AoE DPS
For 16s:
36.15 * 2 + 71.75 * 3 * 0.41 =160.55 damage, less reliable
4 + 3.3 = 7.3
160.55 / 7.3 = 21.99 AoE DPS