There's a reason it's commonly stated in a lot of places that aikido takes longer to become viable than other martial arts.
However, IMO, if you add in these baseline skills as part of the training methodology for aikido, I really do think that it will be at par with all the others.
Hi Mark, I just wanted to add to that point. The following is a translation from Wang Tsung-yueh's Treatise on T'ai-chi ch'uan:
"Friends, you can gain a great deal from a very simple explanation. Let us consider, for example, a few people who have practiced T'ai-chi every day for five or six years, but who are always bested in competition. A colleague asked, "You have studied faithfully for five or six years, but why are you still not successful? Please demonstrate the Thirteen Postures so I can see." What we see in his form is "horse stances," clenched fists, a fierce countenance, and gritted teeth. He has as much strength as an ox, but his ch'i is nowhere to be seen. This is the result of practicing double-weighted. A colleague laughed and said. "You, Sir, have simply failed to understand the error of double-weightedness." Another man said, "I have been practicing without using force for five or six years, but why is it that I cannot even knock over a ten year old kid?" The colleague asked him to demonstrate the Thirteen Postures and noticed that indeed he used no force at all. However, he was floating like goose down and didn't dare to extend his hands or feet. He was even afraid to open his eyes wide. The colleague laughed and said, "You, Sir, are guilty of the error of 'double-floating.' Double-weightedness is an error and double-floating is also an error." Everyone laughed and asked, "How can we discover the true method of practice?"
1) This is exactly the same thing as Aikido. Neither muscular, "external" means of practice, nor blending like the breeze using no force, are "correct". Both ways are not using Ki. If you see no parallel between this story and the stories and commentaries of Ueshiba, Tohei, etc etc on this subject, then you have some serious pondering to do, or are hopelessly closed to the idea that maybe you don't comprehend what the old masters were really talking about when they talk about using Ki.
2) Internal mechanics are not easy to grasp. Evidently it was and is not uncommon for people to practice daily for years and just not get it. Without explicit research and focus on what is right and what is wrong, making progress is difficult. Not getting it, even with access to someone with real skills, appears to be the norm. The idea of getting it just by repeated practice of external mechanics is beyond ridiculous. It will simply never happen.
3) The focus of people like Akuzawa, Mike, etc is to try to distill things and/or put them into Western terms so that people with day jobs can hope to get somewhere with this stuff in a reasonable amount of time. No matter what, it will take longer to get these skills than to get usable skills with BJJ. If you want fast fighting ability, practical external arts with lots of sparring are the way to go, period. If you're interested in the skills that the old masters held in highest regard, skills that have old men doing things that young men can't accomplish, then you have to expect that to take a good amount of time.
If you want do to an art which should have internal mechanics, like Tai Chi or Aikido, yet not bother with actually learning internal mechanics...that's fine as long as you don't care about whether you get much in the way of effectiveness or interesting skills. Some people just like the peaceful mindset and hanging out at the dojo. If they're honest, they probably have the expectation that over the years they will get Ueshiba-like, which invariably will cause some form of cognitive dissonance in those willing to admit it isn't happening for them. Hence the ever-present threads about getting discouraged with Aikido, whether it really works, and so forth. Even if you don't get near the storied levels of Ki ability, it's still the most interesting part to pursue, in fact the only interesting part for me. Without that, most Aikido as practiced seems to be a few joint locks and a lot of wishful thinking. Personal choice.