Ha! This was my response as well....to say Ji (Ti or Fi) and then to consider how it really can manifest in all the functions, or requires more than one.
I don't find ISTPs to be very good critical thinkers, otoh.
Some can be better than others, tho (and some halfway decent).
I find Si and Se to both be rather against critical thinking.
(They look at everything too statically, aren't open to enough possibilities.)
I disagree. Sure, I don't think Sensors are as good at the INTJ (or in general the N) approach to critical thinking, but I think this is primarly down to a difference in situations people prefer to apply critical analysis. I think with Sensors it's much more oriented towards practical problem solving and workable solutions.
For example, my ISTP dad co-owns an earthmoving business and is an extremely skilled mechanic. I suppose most people see mechanical problem solving skills as being obvious: ie this part fits to this part and so on. However, it involves a vital combination of knowledge, experience and insightful analysis of facts.
My dad gets frequently calls from other companies from all over the country, asking him to help out with a problem over the phone. Sometimes multiple mechanics have been tearing their hair out for weeks trying to figure out how to fix a machine. They may have pulled it apart several times over, replaced parts, and tried adjusting everything they can think of, but nothing works. They explain the situation and my dad asks a whole bunch of very specific questions about all the signs the machine was giving off beforehand (eg. vibrations, lack of power, when problems occur), about the work that has been done, and relevant configurations. He almost always comes up with the solution within 10 minutes, without even having seen the machine - much to everyone's amazement.
I find this ability fascinating and I've asked about how he goes about it. Really what it comes down to, "go back to square one, follow the signs and assume nothing". When he describes others' approach it seems like they're just blinding stabbing in the dark, trying random stuff, and hoping for a magical solution. Whereas, he carefully analyses the factors themselves without leaping to conclusions and acts in a very deliberate manner. To me, this really demonstrates the shrewd gifts of Ti and Se. Se in particular gets a bad rap, but with my dad I can see how it basically functions as a fail-safe against inaccurate and unfounded N-style projections, that only distract from and conceal the truth. In a way, I suppose it seems entirely obvious, but then why isn't everyone doing it that way and why are they having so much trouble?
And when I look back over the wikipedia list I posted, I think my dad is very good at all those things. However, if you were to ask him about interpersonal problems, textual analysis, or conceptual thinking, he's at a loss. His skills are very specific to certain applications. Mine by comparison are more broad but are less useful in practical situations.