All of us have a favorite ice cream or dessert, way to fix a hamburger or a favorite beer. In much the same way we also have a favorite technique in whatever martial art we practice. The danger lies in favoring those (Tokui Waza) too much and ignoring the rest of the system that we are internalizing.
In the style of Aikido that I teach I show a broad range of ideas that to me are (and have always been) a part of Aikido; but then again, my Sensei was originally a Judo player before going into Aikido in the same way that Tomiki was in Judo under Kano prior to becoming a student under Ueshiba. Our Aikido, therefore, can sometimes be much broader than so-called more "traditional" forms of Aikido in that it has strangulations and ne-waza and atemi and sacrifice throws and osae-komi and straight line waza and circular waza and hip throws and defensive ideas and offensive ideas and empty hand randori and tanto randori and on and on.
Out of this broad array of ideas any student will naturally gravitate to a small handful that he uses 85-95% of the time. This "favoritism" is due in no small part to his; proclivity to "hit" or grab, stand or go to the ground, or use arms or legs and is heavily influenced by his MA background, current rank and what waza feel "easier" to do (e.g. which waza does his subconscious mind understand the best). Any "favorite" idea that he has will, most esp. in a randori situation, appear over and over esp. as the pace picks up and he begins to work more and more from his subconscious programming and intuitive facilities.
As an example, while watching two senior players recently in a fairly fast session of hand randori, I observed as one of the two continually grabbed the other, did a sacrifice throw and immediately moved into an osae-komi (pinning) position. He had been working and thinking on sacrifice throws into groundwork and was going for any opening that he saw and this involved deliberately looking for an entry into that sacrifice throw.
The problem, as I saw it, was that in order to close with his opponent to the point at which he was able to grab (his opponent) he went by 2 or 3 standing waza that would have been easier to get to and to put into effect, and additionally he potentially exposed himself to several and various waza that his opponent could have easily taken hads he been just a little more seasoned in the hand randori. In short; in order to go for his favorite idea of the moment he avoided the easier idea(s) and exposed himself to defeat because at that moment his Tokui Waza .... was a sacrifice throw.
Since Aikido players are supposed to "do their thing" while standing and NOT go to the mat as a strategic idea of randori or self-defense (both are the same actually) then any attempt to use a takedown/sacrifice throw as a "randori strategy" means that it was essentially planned and deliberate; instead of being an intuitive response to a failed waza; or was happening as the attacker overwhelmed them, with the sacrifice throw occurring as a natural part of that event.
In this case the player doing the sacrifice throw used it as a strategy and ended up in the mount even tho' he has very limited skill sets in ne-waza. He had fallen in love with the sacrifice and in so doing not only gave up standing waza that would have allowed him to effectively control the opponent, he also ended up in a ne-waza position that, given a fully trained groundwork specialist to go against, he would have been toast.
Since he likes and is effective at sacrifice throws, at this point (in his MA/Aikido development) he should work on more fully developing his standing work, learn to let the sacrifice throw happen more naturally (as a resultant of a failure of his standing work) and then work on ne-waza ideas so that the next time he ends up on the ground, he'll have an effective, principled based set of strategies to fall back on; the ne-waza only occurring due to the absolute failure of his standing Aikido and as the end resultant of an effective sacrifice throw.
This is a training strategy that, in my view, is the most effective for self-defense in the street where automatically (and strategically) going to the ground is simply not a good idea given fire plugs, concrete surfaces and the possibility of having his friends dance a tango on your skull as you roll around on the sidewalk with him.
Practice in my view should consist of a session of hand randori, a separate session of kata practice of sacrifice throws that are principally based in occurring off a failure of standing waza (and not as a "take-down" strategy), and then a separate session of kata/waza practice of ne-waza/grappling until full scale "rolling" can occur in a relaxed, principles based (no power games) setting.
Each method should be studied separately (standing, sacrificing, rolling) so that each can develop its own Tokui Waza, specific to the requirements of each situation and based on your internalization of those concepts and principles and their application. Then, when the standing work fails and the sacrifice throw happens naturally, the Aikido player will intuitively "fall" into the best sacrifice configuration for that failure (of the Aikido waza) and then will be able to either roll away or, deal with whatever ne-waza position he may find himself in. As these separate training sessions begin to bear fruit and the player correctly internalizes each, only then allow all three to be expressed on the mat in the same randori session. In this way, any response should be a principled response to stimuli and not a "planned" event; ergo ..... true Tokui Waza.
Trying to blend these ideas and fighting ways too soon and too ineffectively and without a full and in-depth understanding of the principles involved in each of the three will only blur the idea behind Tokui Waza and have a negative impact on each (standing, sacrificing and grappling).
Only by doing each separately can the understanding develop over time that the edges or boundaries between each are indeed small, but easily recognized once understanding is gained. Additionally, the boundaries between each (standing, sacrificing, rolling) should not be breached as a "strategy". An Aikido player stays upright and throws the opponent down. He should not desire to go down with him if, for no other reason, than Aikido players are not grapplers and going to the ground in a real-life self-defense scenario is always a bad idea and should not become the Aikido players "Tokui Waza".
L.F. Wilkinson Sensei
Aikibudokan, Houston, TX