let's say I'm a normal jon doe average pilot,and I don't have acces or interest in any maintenance manual.How would I know of or why should I care about the 25 min off restriction? It's not in our FCOM's or QRH? Then ....
Anyway,you wouldn't use flap 30 for go-around reasons,and maybe ,due to assymetry risk also..
Badly need flap 30? well,maybe burn some more fuel,and use flap 15 or use other airport,or use flap 15 with max brake and reverse thrust...