When i first posted i was still downloading the patch, now i did try the new shells, at least in the Alabino ground, not yet in a real game as yesterday i had other things to focus on.
From my Alabino testing i would say that the WP are mainly geared to decapping, or to avoid that a high camo squishy caps, as the MBTs usually don't have good camo any way so if are not spotted before WP it is unlikely that will be spotted after it. It will surely be more risky for a Sphinx or a PL01 to rush into a cap, while if you do it in a MBT i would say that nothing will be really changed. And i personally think that it is not an improvement for the GLOPS as it further reduces what a fast tank with good camo can achieve, and i am not talking only of the main caps, but also the ones that unlock bombing runs, the drones and the pill boxes, as it is easy to see on the mini map that something is capping them a WP round fired on them will only delay a little the capping by a MBT, that has the HP to survive to the puny damage, but for a Sphinx to be spotted in that cap loosing all the camo when he is still in a cap can be instant death.
As i like very much the concept that the squishy and fast tanks that rely on camo to survive are very rewarding, but only if played by skilled players, i don't like the present implementation of arty in GLOPS, when i will have actually played some GLOPS i will have a more informed opinion about it, but from my Alabino test this is my present, not so informed, opinion.