[rwest]

With no outs, R1 is on first. F9 intentionally drops a fair fly ball hit by B2. R1 advances and is (a) tagged out, or (b) reaches second or third base. Ruling: In (a), R1 is out. In (b), it is a legal advance and B2 is safe on the error by F9. (5-1-1-l; 8-2-10)

I don't understand this ruling. An intentionally dropped ball is an immediate dead ball (per 5-1-1-l), therefore, anything that occurs after that never happened. R1 should not be out. Also, the advance of R1 in (b) never happened. R1 should be put back on first (8-2-10). Even the rules referenced don't support the ruling. What am I missing?