Weird interaction between exercises mode and statics-dependent editors

[Negabinary]

The two type projectors in this example are made to fit in spaces of type hole, because the statics the projectors are given doesn't take code from other cells into account.

The bigger conceptual issue is that sub-editor calculations are now dependent on statics, but exercises mode has this weird special case where one internal sub-editor has two different statics because it comes up in two different places