A. Some day, someone will provide a full and complete answer to that question, but not until that person has time to write a book. In the meantime, here is my two-minute synopsis.
Originally, bare-land condominiums were just that – plots of land on which a trailer or motorhome could be parked. The only common assets were typically a road, some utility lines, a fence, and perhaps an office or clubhouse. The only measurements needed by the surveyor in preparing the registered plan were land boundaries.
In the meantime, developers of condominiums like yours were faced with a dilemma. Before they could sell their projects as condominiums, they needed a registered plan. A surveyor can only file a plan that includes a structure if the structure is there. He or she needs walls to measure to. All very well and good, unless the developer plans a 100-unit project but knows the market can only absorb 25 or 30 units a year. He likely can’t afford to build 100 all at once knowing it may well take three years to sell them all. Ideally, he would like to build his 100-unit project in phases. With a bare land condominium he can do that, as long as he builds each individual unit – in your case townhouse -- within the boundaries of the bare-land condominium unit as shown on the registered plan.
This idea has caught on but leaves in its wake any number of complications for owners, boards, lawyers, and reserve fund planners. Bylaws must be carefully crafted to deal with such items as roofs, eavestroughs, and siding; none of which are either “bare land” or “common property” within the generally understood meaning of the terms, but by any reasonable measure must be treated as common property if the overall appearance of the property is to be maintained.
Hopefully this provides some measure of answer to your question, but you can be sure that the topic will continue to generate discussion for many years to come.