Fellas,
The question came from CFL in 2 PPCLI, so I will assume that the question pertains to CO selection for the Regular Army battalions, and not the Reserves. The latter are a whole different kettle of fish, which I will briefly address below.
Given that there are only 9 Regular Force infantry battalions in the Canadian Army, I can most assuredly tell you that there are far more qualified (and eminently suitable) prospective COs than there are battalions to command. As a result, our current "cream of the crop" have been selected for command. Gone are the days where we had to dip into the deep-end of the gene pool to appoint unit CO's. Also gone are the days where internal politics and "who you know" played a substantive role in the selection process. Patronage and "Regimental Politics" largely ended ended in the early 1990's. In today's Army, only those who are eminiently qualified and possess the right mix of leadership qualities will be selected for battalion command. I need only point out the stellar cast currently commanding (or about to command) the three PPCLI battalions to make my point - LCol Ian Hope (1 PPCLI designate), LCol Stu Sharpe (2 PPCLI) and LCol Wayne Eyre (3 PPCLI). I have worked with all three of those gentlemen, and they are without question outstanding officers in every single regard. The soldiers of today are far better served by their unit leadership than was the case in the late 1980's/early 1990s. Not that all COs were necessarily tainted in those days, by any stretch. The "quality control" was simply a tad erratic thanks to internal politics. As a result, there were as many politically-appointed "duds" as there were "shooting stars". Thankfully, those days are now long over and the guys currently commanding are the best that our Army has to offer its soldiers.
As far as Army Reserve units are concerned, Michael's observations are pretty much bang-on. The Army Reserve has a serious problem with long-term retention and succession, to the extent that unit's seldom have ideal (or even reasonably qualified and competent) senior officers waiting in the wings to assume command. This is why you frequently see "cross-posting" of successful CO's from one unit to the next within a single armoury. Finish your command of a Medical Company without getting into trouble, and then move across the Armoury Floor as a civilian doctor/military Health Care Adminstrator to command an Infantry unit in the absence of a suitably-qualified infantry officer. Don't laugh - I've seen this (or a variation on the theme) happen more times than I can count. How about retired Airforce officers commanding infantry companies? Just ask B Coy, C Scot R.... The same applies to Army Reserve RSMs who change hat-bagdes to cross the armoury floor and have another 2 years in the job with an entirely different unit and MOC. Classification and MOC qualifications apparently mean little at the Reserve CO and RSM ranks. But of course, those are simply the first-hand observations of one malcontent Regular Force officer....
In any case, to get back to the original question I can assure you that there is no need to "parachute" anyone who is not eminently qualified into command of a Regular Force infantry battalion. There is a merit-based command succession list with literally a half-dozen qualified LCols chomping at the bit for each of our 9 battalion command positions. Sadly, all but one of those fine officers will instead end up flying a desk. And if they are so lucky as to beat the odds and attain unit command? Well than see my post in the topic "We are driving good soldiers out of the Army". In today's Army, the "pinnacle" of command ain't necessarily what it used to be....