Wrong. So completely and utterly wrong.
The bike lead that is permanantly attached to the starter motor is directly attached to the battery at the other end


The termlnal is permanantly live
The remote starter post that BMW sell for for the GS even attaches to the starter motor terminal/post.
And i've jump started so many BMW's by attaching the jump leads to the starter terminal that i've lost count.
The RT is identical apart from the fairing covering the starter motor instead of the GS's simple starter motor cover.
You can get a jump start post for the RT. It attaches to the battery and exits above the airfilter housing, allowing you to jump start the RT without removing any body panels. .
So, the bike will not start/turn over if you attach a live jump lead to the starter motor terminal until the ignition is switched on and you press the starter button. No different to what you've done everytime you want to start the bike.