Bob Hunt, a fellow Mainer, has pinpointed the problem: synthesizers
will re-strike a note no matter how short the gap is between notes.
I fight this problem constantly, not with pianos, but with roll-operated
hand-cranked monkey grind organs.  I arrange music for my Raffin
31-note organ, and first test it using the MIDI valve interface
I built into the organ.

First I have to make the notes shorter to get the magnets and valves
to respond, to cut off the pipes between notes.  Then, if I proceed to
print and punch out a genuine paper roll from my computer work, I have
to leave even more gap in the paper to let the organ's valves close and
re-open.  Better crisp and choppy than smooth and sloppy. :-)

Editing note length in standard musical notation is trickier than
in piano-roll graphic view.  My own program has marcato and staccato
articulations, but sometimes marcato is too long and staccato is too
choppy.  So then I have to change, say, an 8th note to a dotted 16th
plus a 32nd rest.  Messy, but worth it.

A friend did play one of my own ragtime compositions on a solenoid
piano, and while he didn't report any run-together notes, I suspect
some editing would have made for a more exciting performance.

Bob and others are welcome to try out my ragtime MIDI files from
http://members.aol.com/knudsenmj/myhomepage/index.html

Mike Knudsen
Bath, Maine