Natural subs VS Forced techniques.

OK, I haven't had the time to really pick my coaches brain on this topic, but I like discussion so here goes:

I have found a certain group of subs have really come natural to me. I seem to have decent percentages on most choke attacks from the Vicegrip, such as Darce, Anaconda, PNT, JNT. I also feel very comfortable with back attacks and the truck, etc.

Where I find I have a serious hole in my game, is from the front headlock position, which is only an angle away from the vicegrip position. I'm strong with the attacks I mentioned from Vicegrip, but once I move around the head, I can not (for the life of me) submit a resisting opponent with an Guillotine, Marcelotine, or any variation of guillotine.
I don't know why, but I just can't get the tap.

Same applies with North South choke. Stew has been showing me some pointers and I am starting to get better at them specifically, but I find guys are rolling out of the position and even though I FEEL like I am putting a lot of pressure on them to stop them from moving, guys can still move.
This is in stark contrast when Stew or Tim (Purple belt) put a North South choke on me: I feel pinned to the ground and can't even lift my shoulder! And if it's a RAT choke I am attempting (Reverse arm triangle), just forget about it. My percentage for the tap drops to Zero.

Anyways I an not looking for answers, because fixing my Guillotines is something that is going to take one-on-one instruction. I am just saying that it seems like there are some techniques that I fall into using quite naturally, and others I really can't seem to nail, even when I really focus and try.

Thoughts?
Can anyone relate?

Practice your weak spots until theyre your strong spots. This will always be the case.

Arm in guillotines still work.. so try Denny's pretzel grip. Marcelotines are NASTY so you have to be missing a detail! They are everywhere and if you can connect your hands and block the shoulder its really high %.
North south chokes are the biggest hole in my game by FAR. Rhassan, Botello and Epstein have helped me get better and each had their own take on them. Having the epstecutioner in your back pocket is also huge but I neglected N/S chokes for a long time because of it. Dont make that mistake but its a must have move IMO.

N/S choke is vital, and is super technical, you are very likely missing a number of details.

Regarding the NS choke it's probably the most difficult choke in the game as far as learning curve goes. It requires a great deal of "feel" and it's very different from the majority of other chokes where you can just squeeze and get a tap. Like even with a darce or anaconda, or other arm triangles, even if you're angle and positioning isn't perfect, you can still usually get a tap if you can squeeze hard enough. It might not be the cleanest choke but it'll get the tap.

With the north south choke you can't just squeeze your way through it. There are a few schools of thought on it, but I'm big on the Marcelo Garcia "shoulder drop" finish. The point is that it takes time and some subs are just more natural to some people than others. I mean there's no question that the NS choke is probably the most underrated finish in sport grappling. Marcelo and his students are amazing with it, and some guys like Jeff Monson and Rani Yahya are. But it hasn't caught on in the competition scene the way that the darce has for example. I think it will, given enough time. I think the Marcelotine caught on before the NS choke, and I've personally spent a good deal of time training with a great grappler that spent a lot of time directly learning under Marcelo Garcia, and even he was having problems getting a clean NS choke on me. He probably did it 6 times in a 7 minute roll and only got a clean choke twice. He said that a year later and he was still having issues figuring it out.

I have horrible JNTs. I think most people have finishes that just don't come naturally to them. Armbars don't come natural to me at all. Neither do Kimuras. Guillotines, darces, RNCs, arm triangles, anacondas, and triangles all come very easy to me. Just work at your weak spots and keep working them and they'll get better.

Also keep n mind that as you get better you don't even really need to be great at everything. If you have a few strong finishes from all of the core positions and the key scrambles then you should be fine. So if you have a solid front headlock game that doesn't involve guillotines, that might be fine. But in the learning stages I would still say to work on what you think needs improvement.

This video honestly helped me the most with my high-elbow guillotine (Marcelotine).

https://www.youtube.com/watch?v=IG1vZUY7AC0

Thanks for the points guys. I will check the video out when I get on a computer that allows Youtube access.