Add that in the first weeks we were infusing (for me D:) like crazy "critter" because you wants better dmg in your exotic, i -blam!- it up with my Suros i infuse it like this: 280>282>288>288>291>297>297 (and not only with my Suros) then i learned that even if you infuse a 280 with a 285 you got a 284 for max, so now im trying to infuse with the max so i keep some weapons and the rest i dismantle but my rate of blue engrams are like this 1/10 (weapon/armor) and with that 10% i have like 25-30% to get one weapon for infuse and the other for dismantle and even with the dismantle my probability is like 33.3% for gettin 1/2/3 weapons parts, so getting weapons parts is very low, even if you keep or "infuse/upgrade intelligent" sometime in the future some of them will be like us or worst.