For some, yes... they may be able to use tickling as a form of light "punishment". However this sadomasochist would never utilize it upon my own submissive, nor would it ever be effective to me as well.
But the use of "never" in a BDSM relationship context is itself a something that can be erroneously tossed around. You wouldn't use it, but this idea of real S&M'ers never use what they love as a tool for 100% domination, punishment, even sadism seems to limit what should be the very essence of freedom from the average "plain" relationship world. I know for affect that the one sub who got tickled as punishment was in a 24/7 lifestyle and not a light player.
How thrilling it would be to live within a relationship where I could give (in topping mode), or receive (in bottoming mode), that which I hated, or that which I craved - turned to a darker end - as a way of truly dominating me whether I’ve done something wrong or just because my partner is feeling naturally extra sadistic and I am there to support her even if it‘s not always a place I may want to go. I’m baffled that I (and to some extent the original poster I’m guessing) seem to be the only one who sees the potential energy this relationship could have. It’s not for everyone, but to banish this practice on principal seems pointlessly authoritative.
People in these relationships are individuals. Which means "BDSM relationship" can have as many facets to it, different colors and textures, as what is considered normal, at least on the surface. Open marriage, same-sex, bigamy, polygamy... and normal vanilla relationships on the surface with who-knows-what going on behind the scenes - none of these are BDSM relationships, yet all have their own uniqueness and flair, both in the common structure in the relationships and the singular nuances the individual partnership has.
And who "discourages" this practice? The BDSM rulebook? That's one of the main things that put me off in the beginning - and even now - when joking PEP, investigating The Leather Rose society, etc. when I was first learning about myself, and others out there that were like me. It was such a drag to know that a subculture I was leaning toward could be a repressive and 'rule-ish' as the vanilla world.
Don't talk to anyone wearing a collar without permission. Black leather and metal spikes is the commonly accepted dress code. No play if alcohol is in use. That kind of thing. I'm not talking about people being reckless - I mean no exceptions,
ever. How is it that people in many cases considered outsiders or abnormal start setting up rules to create classes of 'outsiders' or 'abnormals' within their own subculture? In my early years, the contradictions at times made it all seem like I was partying with punk rock Mennonites.