i can understand some of the points made on combining arts. like swimmingdragon said about learning hsing-i to get the explosive power, and how that helped his liu ho ba fa. but i think you could still gain all of these qualities that you study seperate arts for if you concentrate on one and learn it deep enough. these arts all contain explosive power, for example. they all contain chi gung, for example. the question is, are you willing to bore yourself to death practicing just one art to discover all it offers?
leiming, you said something i’d like to discuss;
The combined affect of learning two or three internal arts together is vastly greater than the sum of learning just one of them.
i think that’s mad incorrect. i’ve heard of people who learn only one thing for years and years. all they practice is this one thing, let’s call it a “technique”. doing only this technique for hours and hours, they eventually learn how to use the technique for offense AND defense. they soon discover that this technique can be applied to not only punches but to kicks too. this offense/defense capability is common is alot of the things we learn in internal arts. it’s like mike patterson. ever see his video clips? he can take one hsing i element and show you defense/attacks verse punches, and kicks, can use it to lock, to throw, use it with heavy power (more pushing) or shocking power (more penetrating), etc.
so think of all the “techniques” you’ve learned thus far. if you have been practicing for a while then that’s quite a few no? now, if you were to slice that number in half and only practice those, but still practice the same amount of time, then you’d learn so much deeper about those, simply because you’d practice them so much more. in the end, you have greater skill becase instead of knowing 3 internal arts at a lavel of 5, you know one at level of 15. LESS is more when you do the math. and they all contain the same mechanics, so it seems to me to only make perfect sense to stick with one. sure variety is the spice of life, but no one said the internal arts should be spicy. one thing is meant to be drilled until it becomes the most boring assemblance of moving body parts known to man. dull, boring=bland taste, not spicy.
“Yankees, Mets, Red Sox, its all baseball”
no doubt. but the best teams have some things in common. they all have good players that have been on the team for a good number of years. for ex, the yankees…team of the decade. jeter, bernie, mariano, petitte, and posada have all been on the team for at least 5 years…some more, and they all want to stay yankees. soriano, hensen and johnson will (hopefully 
) stay with the team for a while too, which further ensures their strength. they all know that they gel as a team and that a team that has played with each other for a while is a great ball team.
when good players stick on one team, they gel, start whoopin a$$ consistently and become dynasties.
the analogy to the internal arts is that when you have a good system with sound principles and methods (any internal for example) and you STICK with that one art, you begin to gel with it, it becomes second nature and you start whoopin a$$! if you go from this art to that one…sure, it’s all baseball, but how well to you get to know the team you are playing with before you bounce to the next?