Interesting idea, though I'm not sure whether some behaviours are working as intended. For example (ROT13): jura gur fvghngvba ybbxf yvxr: (11)(KK)|K... , jurer 1 zrnaf cynlre punenpgre, K zrnaf obkrf naq | zrnaf jvaqbj obeqre, gur guvat V'z rkcrpgvat gb unccra jura chfuvat evtug vf ..(11)|(KK)K. , ohg gur tnzr vafgrnq cebqhprf ..(11)|(KK).K
Another example is kinda like this (ROT13): chfuvat evtug va fvghngvba (11)(KK)|2.K. , jurer 2 zrnaf nabgure cynlre punenpgre, guvf jbhyq erfhyg va 2 naq K fgnpxvat ba rnpu bgure.