[PP] [MA] Unobvious advantages and limitations of TK Grab in combat

[Thökk]

I read TK grab carefully and came to conclusion that with a decent level (10 and up, especially short range version) and decent IQ it can be quite a serious brawling, judo, wrestling opponent.

It has its level in BM, it has its level in ST, It has your IQ in DX.
It doesn't have HT or HP. It gets certain benefits of being invisible.
It can't be hit or damaged, it can't be thrown away (unless you hold an object or weapon to hit), it doesn't(shouldn't?) have disadvantages from sitting, lying as it is just you moving your TK Grab around, it doesn't have anatomy or space, it can perform maneuvers that otherwise risk injuring you or maneuvers that otherwise require you to have long preparation, risky positionioning from climbing or even space that you wouldn't be otherwise able to fit in (pulling somebody by their ankles off the ledge, pushing or pulling somebody into a line of fire or active hazard, like fire, electricity, water, etc.). On the other hand TK Grab doesn't have a body or legs to leverage.

All in all, I think, how and where you can apply force (whilst being invisible) should significantly impact what you can achieve.

But I am not very knowledgeable about GURPS rules (or physics, really, it's just all intuitive assumptions above), so I want to challenge my assumptions and ask you all what are some "hidden" advantages and disadvantages a TK Grab brawler/wrestler/Judo adept has compared to a human one. Are there some tips fleshy opponents can benefit from or trick to pull off against TK Grab? Can a Psychokinetic develop a new Style and set of Techniques for TK-assisted martial arts?

[Varyon]

So I don't have Psionic Powers, and will thus be going largely off baseline TK (I'm assuming the only difference between that and TK Grab that is relevant here is that the latter uses IQ in place of DX).

As you note, the indestructible nature of TK's "hands" is very useful, as is the fact that they basically fly rather than needing to change posture or similar. You can also use it to grapple your foe in a hostile environment - pull them into traffic, off a cliff while restraining their hands so they can't catch themselves, deep underwater, in a conveniently-placed vat of acid, whatever - without risk to yourself. A realistic downside - although I don't think this is actually stated anywhere, and generally doesn't fit the fiction* - is that the TK hands are functionally weightless and unanchored, which should make it harder to actually hold someone in place, absent grappling their legs. You'd probably need TK BL comparable to the target's body weight to actually prevent movement when you're grabbing them just about anywhere else. I'd probably say you need (TK BL)x(TK Move) equal to or exceeding (Target weight)x(Target Move) to hold them in place. If doing things that way, an option the target has is to get out of your TK range (for default TK, this is 10 yards).

Note that drawback isn't RAW, and may be a bit overly complicated at the table.

*Although in fiction, characters with TK normally have rather powerful TK - enough to lift the target into the air, which as noted above would be enough to prevent them from moving.

[Thökk]

I assumed TK Grab has virtual mass necessary to apply force and generate inertia and uses itself as its own anchor, but I guess it can't benefit from getting even more stability by any means.