Jimlad I did not suggest that it would be done soley by ferrys and cruise ships! To secure bridgeheads you would usually land light troops, hence why we have the Royal Marines.
Containing Mount Pleasent isn't too difficult! Lets face it 4 Typhoons would be very highly tasked with invasion forces as well as trying to maintain air superiority as well. Portable air defence capabilitys can be placed to stop the comings and goings from Mount Pleasent and then you have it conatined!
We know the frontline fighting troops on the Falklands are only a fraction of the personnel based on the islands.
Yes I am assuming that intel wouldn't give us much more than 24hrs warning (in which time you would hope assets could be deployed south to reinforce) but we have been known to misinterpret intel before!
May of been vague before but what I am trying to get at is that there is an errosion of the deterrent (carrier strike force etc) while the Argies are actually increasing their defence budget and their escalation in aggressive stance on rights of passage for shipping in the area! In areas of defence I sometimes wonder if we learn!