There's no way to answer that without knowing the 'ler, the 'lee and the situation. You know that. 😉 Either way, I'm not sure what insensitive there is to break someone quickly. Toying with them is fun and if a 'lee taps out, the tickling is over. I haven't met too many people who I couldn't tap out on-demand, but to me it's more a fun way to end a session than it is something you want to focus on.
I love questions people write when they're horny. 🙂=)