Right, but you're calling into a huge dynamically typed external app, and that may have entirely different conventions for reasons that make sense in that app (

Right, but you're calling into a huge dynamically typed external app, and that may have entirely different conventions for reasons that make sense in that app (here excel). Normally, 30 is crazy. But in excel? Who knows... Also, too many isn't a problem, they're optional, so in practice you'll be treating this as a varargs; there's not much cost to having a few more args. I haven't used this function, but I suspect I'd rarely call in directly anyhow, instead making sane wrappers for various apis you actually care about which in turn call this internally, making the direct call details even less relevant.