Roland System 100m

On page 47 of Roland's "Practical Synthesis for Electronic Music" (which is basically the 
Roland System 100M 'manual') it states

"The multiple jacks cannot be used in place of a mixer.  If two outputs are connected to 
the same multiple jack set, the result will be what is effectively a short circuit to both 
outputs which could cause damage."

The first part I buy (obviously) -- it's not a mixer.

But I never thought that accidentally connecting two outputs to a multiple could cause 
damage.  It happens -- that one puts two outs into a multiple -- even if you try hard not 
to.  (In fact did it last night -- didn't get the result that I wanted, I tracked down problem 
and corrected).  I've never noticed any damage, never worried about it.   

In fact the manufacturer of my other modular (Blacet) says don't worry about that sort of 
thing -- his machine can take it.  Is the 100M a delicate beast?

Best

Robert