This might seem like a really silly question, but I'm gonna ask anyways 
what, in your personal experience, is the most effective way to crosstrain?
for example, I've recently begun training Krav Maga - I've also entertained the thought of training (in the near future) in BJJ / or some form of ground work, maybe Sambo... although I'm also lured by FMA's like pekiti tersia (although there's apparently none whatsoever in my area - DC metro), and arts like Serak Silat (also... none in my area). So I'm researching Amok!, but thus far am having little luck with that (... the local tribes email dont seem to work). Ok, enough digressing - the point I'm gonna be driving towards is how much time does one need to spend on a particular style/art without shortchanging it?
Personally, I'm finding that Krav is a relatively demanding workout, so I train 3 times a week with a day off in between - until I get in better shape (which I do expect to), I'm a little sore on those off days.
in addition I'm curious as to what peoples opinions are on training more than 1 thing at a time? is retention/learning impaired by splitting ones focus on two different arts?
appreciate any feedback - thanks
dok

what, in your personal experience, is the most effective way to crosstrain?
for example, I've recently begun training Krav Maga - I've also entertained the thought of training (in the near future) in BJJ / or some form of ground work, maybe Sambo... although I'm also lured by FMA's like pekiti tersia (although there's apparently none whatsoever in my area - DC metro), and arts like Serak Silat (also... none in my area). So I'm researching Amok!, but thus far am having little luck with that (... the local tribes email dont seem to work). Ok, enough digressing - the point I'm gonna be driving towards is how much time does one need to spend on a particular style/art without shortchanging it?
Personally, I'm finding that Krav is a relatively demanding workout, so I train 3 times a week with a day off in between - until I get in better shape (which I do expect to), I'm a little sore on those off days.
in addition I'm curious as to what peoples opinions are on training more than 1 thing at a time? is retention/learning impaired by splitting ones focus on two different arts?
appreciate any feedback - thanks

dok