Hi, Jim -
That’s not 100% exactly totally correct.
What is true is that trading spreads can be a cumbersome hassle on C2. But to be precise, if you buy the long position first, then the complementary short position should be recognized as a component of a spread and will receive favorable margin requirements. (I.E. the spread will be “recognized” as a spread, and you won’t, for example, be hit with naked short margin requirements on the short leg.)
This is true only for plain vanilla stuff (calendar and vertical spreads). Anything more complex gets more dicey.
So, while it definitely needs a lot of work, I wouldn’t quite agree with Jim’s assessment that it’s impossible to trade option spreads at C2, at least from a margin-use perspective.
The more challenging aspect is not in C2 margin requirements; it is that it is not possible to buy spreads at a debit limit price (or sell them at a specific credit amount), functionality which is now commonly available on most broker platforms. In that sense, Jim is correct that you do need to leg into positions one leg at a time. This is something we need to improve.