Does the defense bonus from shields stack with cloaks?

Question

In Gurps (4th Edition), does the DB given from a shield stack with the DB given from a cloak? If so, isn't it possible to raise your dodge skill untouchably high?

Default dodge of 8 plus 2 from a light shield plus 2 from a heavy cloak means you dodge on a 12 (~70% of the time). All-out dodging (additional +2) would mean you dodge on 14 (a whopping ~90% of rolls).

Answer 1

This is answered in the Official GURPS 4th FAQ 3.4.1.11..

A cloak is used like a shield – as implied by both the Cloak skill write-up and the cloak's listing under Shields (p. B287). It gives DB only when partly wrapped around one arm or held in one hand, and then used to brush incoming weapons aside (either on its own or by padding the hand enough to allow it to assist) and to partly obscure the body from frontal attackers. Worn on the back, it doesn't do much at all. Well, a heavy cloak might add +1 to DR from the rear, but there's no DB.

In any event, you can only benefit from one source of handheld DB, whether it comes from a shield per se, a buckler, or a cloak. These things never "stack."

Answer 2

I don't have enough knowledge of GURPS to say for certain that that's legal, but let's assume for a second that it is and the GM doesn't feel like house-ruling it. This brings us to the second half your question: Wouldn't that make the character untouchable? The answer is no; the GM can always do one or more of the following:

1. Throw that PC attacks which can't be dodged for some reason. (E.g., they explicitly bypass dodging, the PC is trapped in a confined space where they can't dodge, the attack is non-physical, &c.)
2. Have someone pin the PC down with so many or such heavy attacks that they are forced to all-out-dodge constantly, knowing that (a) they will still dodge it and (b) they will be too busy dodging to interfere with whatever else the villain is up to.
3. Throw that PC challenges which aren't combat. (E.g., If the PC becomes renowned as an untouchable fighter, have a clever opponent try to deal with them through debilitating poison in their food, having them pursued by the law on false charges, &c.)
4. Catch the PC when they're not fully equipped/dressed, or have a stealthy opponent steal their equipment when they're not in a good position to buy replacements immediately. (No equipment = no bonuses!)
5. Penalize the PC for running around with all that equipment on all the time. (E.g., heat exhaustion penalties for wearing a heavy cloak in summer. Or just have it get snagged in doors, on bushes, &c. :P)

Those are the basic categories of response that I can think of, but there are probably more.