I first started with Spencerian. Did not know about any other cursive. I stumbled upon John Bland round hand sample on the internet super highway. Blown away, I kept practing the round hand using the Spencerian guide. Now.. I can't separate the two.
Ken, anyway method to separate them? I love both cursive and I wanted to be able to separate them. For Spencerian, I use a more rigid flex, and for round hand a very easy to flex nib. The marriage of Spencerian majuscle with English Round hand miniscule, I think is my current handwritting.
I believe that this is a common problem. The two styles are ostensibly similar but are, in fact, entirely different. Spencerian majuscules can sometimes look good with Copperplate minuscules but the minuscules alone, of both styles, never mix well IMO.
I'm sorry that, to the best of my knowledge, there is no short cut here. They really do have to be learned separately and thoroughly. In your position, I would make a definite decision as to which I wanted to learn first, and then I would concentrate solely on that script until I was confident that I knew it really well. You'll know when you've reached that point, as the lettering will flow effortlessly under the hand.
Then the process can be repeated with the other style. When you have equal and total control over both styles, you should be able to write either style without effort.
None of this, is particularly difficult; it just takes time.
Ken