Er. Looks like this question is very important to you? Seems like you asked it about 10x.
Well, it's a question of what your guitar can "handle". Some multi-voiced (MIDI or Acoustic Pick-ups) can support TRS to you can "Y" cable into different outputs. I think my Michael Kelley Hybrid Special is like that. Some Godins I believe are like this too.
However for most guitars and most amps, they can only support unbalanced signal. They cannot support balanced signals (needing 3 contacts), and therefore any added expense is wasted. When you open up the amp or guitar, they only have 2x contacts. Basically the Ring (R in TRS) is shorted when plugged in, so it's electrically equivalent to Sleeve (S in TRS), since you only have two different contacts.
Some cables have more 'runs' or wires, but it's done for redundancy and added noise reduction. For balanced cables, you can pay extra for something like the QuadStar:
As a Engineer by education, whose taken very technical electronics and signals courses at the under-graduate level, most of what people sell in cables is 'snake-oil'. Get a nice, flexible cable that has enough stranded/braided copper with some shielding and that will be get you 95-99% of the way there.
I would, and have plugged in TRS as a patch cord for a guitar in a bind, but I don't do it regularly. Spend the $ on better quality unbalanced 1/4" cable, vs. lesser grade balance 1/4".
Like the guys have said, there's no advantage. I have a Godin that can use a stereo cable, but that's 2 separate signals + earth, rather than TRS.
The answer to the great 'guitar cable' question is not usually in the guitar, but in the amp and/or pedals. Some pedals have a buffer that will eliminate many of the issues people perceive as a problem with their cable sucking out high frequencies, while some will suck away far more high frequencies themselves than the worst quality cable. Worth bearing in mind that many *GREAT* guitar tones have been created with nasty, high capacitance curly cable, while many nasty ones have been heard from players using top-end amps, guitars and cables - you never saw Jimi use George L's.
However the place to deal with this is the amp. I first realised this varied when I went to look for an amp and took my guitar AND processor with me. Some amps were completely unaffected when swapping from guitar direct to G + P, while others went from glorious to ghastly. A while after this I got into amp building, and then one day tried plugging into a bought amp with a Bad Monkey in front of the guitar - tone suck so bad it was not actually playable - really! So I pulled the amp apart and started replacing the first resistor in the signal chain, eventually finding a value (about 23K IIRC) that would let me plug most things in without a noticeable change in tone. When I build an amp now it's one of the things I try to optimise.
Like I said, some amps suffer really badly while others not at all, and it's not necessarily this one thing that affects the tone (many valve amps use 68K as standard) but the place to deal with tone suck is definitely at the amp if that's possible.
I would just add that you should look for cables that are no-microphonic. Some really cheap ones are so bad that you can hear a thud in your amp when you step on them and if you slide them around on carpet, you can actually hear it. And when you play with any volume, they pick up all those vibrations and it sounds muddy and inarticulate. It's due to the construction/materials used. Good ones will say something like "conductive PVC layer under the shield conductor". If you buy a ready made cable with Mogami or Canare as the base cable, you're fine. Monster brand is generally OK, but you pay too much and they usually use cheap plugs that are jazzed up to look esoteric and expensive.