Indeed, no expert appearing before you could discuss these issues with total certainty, unless his primary goal was to convince you. It is impossible to discuss these matters with complete certainty, because there are no provisions that expressly deal with this.
In my view, the very definition of a prerogative is that it can be exercised on a discretionary basis. When a prerogative can no longer be exercised in certain circumstances prescribed by law, it is no longer a prerogative. For a prerogative to be a prerogative and remain so, I believe it must respect the Crown's discretion—in other words, the Prime Minister's discretion as senior advisor to the Governor General. So, the Crown's discretion to exercise that power, when it sees fit, must be respected.
Could there be an annual prorogation, such as in Great Britain? Probably, but that would not prevent other prorogations from occurring during the year. Insofar as the Crown's discretion to prorogue Parliament when it sees fit is respected, in my view, the nature of the prerogative remains intact. So, that was my first point.
The second point is that the limitations you referred to must not be such that they would alter the prerogative. They must not, in terms of their number, significance or scope, be of a nature that would ultimately invalidate the power to prorogue Parliament. Basically, any conditions placed on the exercise of that power must not be so onerous that, once again, they alter the spirit of a prerogative which is linked to the Crown's discretion.
However, is it conceivable to introduce restrictions that would mean a government would suffer the consequences of proroguing Parliament? In my opinion, that is certainly conceivable. Again, it would be possible only if the prorogation power were not altered. In other words, those restrictions must be sufficiently explicit on paper for one to conclude that the prorogation power is not altered and that what is at stake is not a Crown prerogative.