[Q]

That's what I did now in SE IV Gold demo:

Troop 1: Cockpit, 1x ground cannon I, 1x small shield III generating 60 shield points, 1x small combat sensor III, 1x small ECM III. Total damage resistance without shields 10kT, with shield 70kT!

Troop 2: Cockpit, 1x ground cannon I, 1x small armor, 1x small combat sensor III, 1x small ECM III. Total damage resistance 9 kT.

You must keep in mind that the shield generator has a damage resitance of 4kT besides its shield generation ability! So this design was the closest the equal damage resistance of the two designs I could imagine.

If the shields work, there should be an important difference in the performance of the two designs in ground combat: 9kT against 70kT resistance!!! However this is not the case.