If you never even touch other characters, your understanding of the game is going to be necessarily limited. Just sayin'
That's the only reason that I've used other characters in SC games. That was my way of saying that I'm Sig in SC, I really don't like other characters play-style or story-wise etc.
No way, it's way easier to understand how your opponent thinks when you know how it feels to play their character.
I'd also argue that you don't really understand the matchup until you learn how their matchup against your character is different from their matchups against other characters.
I guess it's possible to know all this without ever playing another character, but it's so much easier to get a handle on their options at any given time and grasp the strengths and weaknesses of a character if you experience them yourself.
How are you going to fully understand how a tool is used if you never try it yourself? You simply can't hope to know the subtleties of a character if you rely on others to show you.
I agree 101% Not entirely necessary to play other character to know defense vs them, but it DOES help a lot more when I know if my rivals have to (or will to) do "1-input" or "2-input" moves, just for example. Like, when I watch any Sophy player walking diagonal-backward, I often expect them to 11_77AA, & that gives me their "tell" for me to ready ahead my 44B by just walking backward then pressing B on reaction to their action, which often happens to be 11_77A. Its kinda how I calculate my bets in matches. Measuring my rival's next move by
RANGE also helps a lot if I know their 66_33_99 moves ahead to counter them.
Another thing is when their range (or any) move has a DOWN-input (like Sig's 2A+B), they have to stop before input DOWN or else they'll get a 22 buffered. I watch the slight pause & my reaction is to counter, often with b6 if they are at range.
EDIT ADD UP:
Another thing I wanted to add up to the "know character's input" is that, when a Sig is backpedaling it is unlikely for a 4K to come out immediately, because the player has to halt the 8wr or else a 44K would come out instead of 4K.
To any new Sig player, the character's input are kinda arranged towards their meant purposes by the developer's design. In other words, the input itself gives a hint of how (& when) to use certain moves at certain situations.
For example..
4K, 4A, 4B "are to be used" during: 5Neutral, 6_2_8Step, 66_33_99_22_88Runs.
11B, 44B "are to be used" during: 44_11_77_22_88Runs. I use 22_88Runs to lure my rival to High (mostly with 66A moves) then I TC by sliding to 1_7+B. Is very easy & effective.
6A, 6B, 6K "are to be used during: 5Neutral, 4_2_6Steps, 44_11_77_22_88Runs.
This is not mandatory, but for me it goes very well when I apply these during battles, EVEN at offline.
Now in SC5, Sig's 6K is SC4's 4K, to me that means that our favorite TC-safe-mid kick is now meant to be used while backpedaling. But, SC5's 66K seems to have TC again (not sure, but if so) that means that regardless of missing 6K during a 6Step & getting a 66K instead, will result in a TC anyway. Making it simpler for Sig to TC between 6Step & 66Run.
SC5's 22_66A have TC, more simpler to lure-in & punish High Horizontal from rivals, because Sig can 22_88Run to "bait" rivals into AA, 66A etc then react with A.
For what I've seen, Sig's hor/ver counter game sums up to: 22_88A to TC-punish High Horizontals & 22_88B to dodge-punish Verticals. B+K to GI Hor-mids, as usual like in SC4.
Another mix I speculate is the new 66A mixed with the new B4. Both have long range, blue-flash effects & similar sound at startup. How I would mix them? I would B4 often until my rival get used to step it (even if I get punished) then surprise them with 66A. Might sound dumb to some, but I'm optimistic about thanks to how is that the new QuickStep seems to work & how is that Horizontals & Verticals are finally working appropriately & not like in SC4 were some Verticals tracked more than Horizontals & some Horizontals were stupidly step-able even agA, lol dumb programmers, but thanks in the end for SC5's QuickStep.
It wouldn't surprise me if 22_88A is launcher-punishable. With it, I'm gonna try to time my rival to counter both HighHor & Vertical options with a well timed QuickStep followed by A. Not at close range tho.
Btw, this is just me speculating optimistically. Heheh, yesterday I dreamed that was playing SC5 at its release date with some friends in a mall, & Sig looked like SC2's NM n_n