Thinder
Did you READ the topo on Corrosive Shells?
While the effect is active, incoming damage from all sources is increased by 25%, and all attacks receive a +20 bonus to their armour piercing value .[
Now how is 25% increase DMG on ALL weapons not "giving necessarily more oomph"? And I have absolutely no problem finishing a busy CZ with that reduced load, I do it 5/6 times a day.
Now obviously, if you waste shells, corrosive or not on active shields it's not gonna work for you.
I did not only read the wiki article, I also TESTED it under real combat conditions in an all-Frag build (i.e. only Frags to drop shields) and screening shell is BY FAR the superior mod in ALL CASES, including killing Anacondas, Type-10s, Corvettes, and Cutters. The increased fire rate BY FAR compensates for any other mod you could put on a Frag. Having four large Frags and two mediums, all with screening shell, makes your Python Mk2 a spitball of death. You could put corrosive on one of the mediums, but it will not increase your kill time so significantly that the reduction of ammo is warranted. Now, if you are going for a single assassination mission build, you could do it (and replace High Capacity with Rapid Fire, see the other convo) but again: it is not necessary and does not improve your performance too much. Again, I've tested this, otherwise I would not make that statement.