That question seems really obvious to me.
There really isn't a reason to "feel out their skill level" or anything. If the person was capable of seeing those things on their own, they wouldn't be asking for help. If they keep getting beat by the same thing over and over again, obviously they either don't understand what they're doing wrong or they aren't able to come up with a solution on the fly. There is absolutely no reason not to explain it to them if it's obviously tripping them up. You can't solve a problem you don't know exists. What happens to lesser-skilled players when they get overwhelmed like that is that they just get desperate and start doing things to avoid the situation in the first place, which means they'll never learn, and as soon as someone else can put them in the same position, they'll start losing to it again. It's the easiest way to make someone quit the game or adopt a scrub mentality.