Martin Aedma is quite well-known for his excellent tutorial filmed by Christian Graugart and given the memorable title, "Estonian Guard Passes from Hell". Aedma's treatment of passing has probably influenced my top game more than any other video.
I was really stoked to discover recently that he maintains a detailed blog.
It has some fantastic insights and extensive accompanying videos that go into real depth on a variety of positions. I particularly like his take on the concepts of posture and pressure.
In case you haven't had a chance to enjoy his writing and videos, it's definitely worth checking out:
http://martinaedma.bjj.ee
Later 
I've been subscribed to his youtube channel for quite awhile. I like how he focuses on an idea then shows examples on how it can be applied rather than a tech here and there.
I like how he mixes Bjj and wrestling.
Great blog!
Thanks for the info- great blog!
Great blog and that guy has a great outlook.
One other thing he talks about that I think is very insightful is that he believes the sitting guard (he calls it seated guard) should be the foundational open guard (the "default" open guard) and used to transition to other open guards like spider, DLR, X, Z, etc.
The case he makes very much corresponds to my experience. Namely, that without the necessary controls required for one open guard or another (e.g., the hooks for X guard, the sleeves for spider) you are vulnerable to being passed quickly.
So for instance, if you find yourself lying flat on your back without controls, rather than try to establish controls from that position of weakness, it's better to immediately go to sitting guard and reset.
Perhaps guys that can invert at a high level can get away with lying flat without controls, but most of us don't have that expertise, especially with a quick, strong, or heavy opponent. And those inverted guard guys are always looking to establish their own controls quickly, which can be difficult for non-experts. What's especially risky is if the tough opponent gets control of my legs lying flat, things can go bad fast.
To me, it's more straightforward to reset to sitting guard, where it's much easier to block grips on my legs and turn the attempts to do so into armdrags.
Anyway, I was sometimes getting in bad positions from open guard but couldn't put my finger on why. But when I saw Martin's discussion of this sitting guard default position, it all started to make sense how I sometimes got in trouble.
This topic sums up what I like so much about Martin's approach, it's not a single move or even series of moves, but a whole strategy based on experience and empirical principles.
I highly recommend checking out those sections on sitting/seated guard.
Videos on Basic and Advanced Seated Guard:
http://www.youtube.com/watch?v=6DOHDr5t60E
http://www.youtube.com/watch?v=Wsh7_X1U7OE
Almost all the top grapplers reset to a seated guard when they are without grips.
Having said that, I think seated guard/butterfly guard is the most time efficient guard to learn because it's the only open guard you can use in nogi and gi without a significant change in effectiveness, it leaves to almost totally protected from leg locks, and it allows a very efficient(most?) sweeping mechanism (xguard).
Agreed on the sitting guard. I emphasize it as well.
I've been trying to work sitting guard into my game lately, but have struggled with a few things. I'm a old beat-up brown-belt that teaches more than he trains for one, but my main issues are:
I can't really use butterfly guard due to a bad knee. I like using reverse de la riva and regular de la riva, but my left knee locks when compressed too much.
My main issue is not being comfortable without a connection to my opponent/training partner when in guard. I get too reactive and many times allow my feet to get controlled.
Any tips?
I'm on SWhittier mailing list and a member of MGinaction, so have some help. I would appreciate any other advice though.
Ryan, email me when you get a chance. Let me know what about butterfly bothers your knee and I'll get back to you as soon as I can. info@40plusbjj.com
Ryan Thatcher - I've been trying to work sitting guard into my game lately, but have struggled with a few things. I'm a old beat-up brown-belt that teaches more than he trains for one, but my main issues are:
I can't really use butterfly guard due to a bad knee. I like using reverse de la riva and regular de la riva, but my left knee locks when compressed too much.
My main issue is not being comfortable without a connection to my opponent/training partner when in guard. I get too reactive and many times allow my feet to get controlled.
Any tips?
I'm on SWhittier mailing list and a member of MGinaction, so have some help. I would appreciate any other advice though.
I have the same problem,is it your meniscus? I injured mine and whenever It gets compressed or twisted it locks up.In my opinion, butterfly guard isnt really a guard you wanna hang out in, if you do you give the guy a chance to start flattening you out and compressing your hooks to your butt. So what I like to do is start at a distance and control it by using my hands as frames keeping him at a distance until I can hand fight and secure the proper grips for the sweep, then I quickly scoot in and insert my hooks and sweep without hesitation while making sure to fully follow through with my hook to not create space and to set my self up to pass to mount. Hope that helps.
GCBJJ42 -Ryan Thatcher - I've been trying to work sitting guard into my game lately, but have struggled with a few things. I'm a old beat-up brown-belt that teaches more than he trains for one, but my main issues are:
I can't really use butterfly guard due to a bad knee. I like using reverse de la riva and regular de la riva, but my left knee locks when compressed too much.
My main issue is not being comfortable without a connection to my opponent/training partner when in guard. I get too reactive and many times allow my feet to get controlled.
Any tips?
I'm on SWhittier mailing list and a member of MGinaction, so have some help. I would appreciate any other advice though.
I have the same problem,is it your meniscus? I injured mine and whenever It gets compressed or twisted it locks up.In my opinion, butterfly guard isnt really a guard you wanna hang out in, if you do you give the guy a chance to start flattening you out and compressing your hooks to your butt. So what I like to do is start at a distance and control it by using my hands as frames keeping him at a distance until I can hand fight and secure the proper grips for the sweep, then I quickly scoot in and insert my hooks and sweep without hesitation while making sure to fully follow through with my hook to not create space and to set my self up to pass to mount. Hope that helps.
Anything specific you've done to prevent damage to your injured knee when using butterfly guard? I have the same problem. Its why I've stuck to closed and half guard more recently, but I think I made my opinion of seated guard clear above.
I always try to sweep to the opposite side, but if I have to I just make sure to use a following through motion if I try to snap my leg out quick it usually locks.
<blockquote>SWhittier - Ryan, email me when you get a chance. Let me know what about butterfly bothers your knee and I'll get back to you as soon as I can. info@40plusbjj.com</blockquote><br /><br /><br />I've had a meniscus repair surgery. I'm not sure if the repair didn't stick or scar tissue is the problem, but my knee completely locks when compressed.
Half guard is where I'm most comfortable now. I like playing knee shield, de la riva and reverse de la riva. I like being connected to my opponent. I'm slow and lazy.
Martin's blog is excellent.