A basic military tenet is this: there is rarely any strategic surprise; but there can always be tactical surprise. I could give a thousand examples.
So - was the Snap Election a strategic surprise? Absolutely not: any Team Corby chappies wargaming the political future after he was re-elected in September would have had it on their list, and - fatally - indeed they obviously did. We'll come to that in a moment.
Was it a tactical surprise? Oh, yes. And conforming nicely to British military doctrine: a deception plan in advance, totally secrecy and radio silence beforehand (fascinating to speculate exactly who knew - the true Teresa Trustees); then strike like lightning.
With tremendous success, because the announcement clearly got right inside Team Corbyn's decision-loop. So all they could do was react with tremendous predictability and trot out their rehearsed line: "bring it on; we're not afraid", hotly followed by putting on a 3-line whip for the Parliamentary vote required to crystalise May's intent. So now everything that follows is on May's chosen battlefield, and - even if she didn't consider it prudent to fire up CCHQ ahead of time [see 'secrecy' above] - at least Core-Team-May is a hundred times better prepared than, well, anyone else on the field.
This reveals the stupidity of the opposing forces, who have forgotten Drew's 4th law of politics: the lines of logistics in politics are short. Very short, assuming everyone (except Gordon Brown of course) has a mobile 'phone. This means, inter alia: no-one in politics needs to be bounced into an instant reaction because (a) any politico worth their salt can play for time (being measured here only in hours, or a day at most); and (b) in a matter of hours you can convene your best brains, thrash out a serious response, and hurl it back into the fray.
In this instance, they should at very least have blown up the narrow bridge across which May was forced to march, namely the requirement for a two-thirds majority. Even if she had a Plan B (and we may guess she did) you've already won yourself even more time: and if you can't come up with a workable slogan to counter the inevitable chorus of "frit frit frit" you've no place in Team Corby HQ.
Instead, they remembered that the last time they discussed a snap election - several months ago, in the abstract, with nothing concrete in front of them - they concluded we'd better say OK. And that was what they had in the locker. "OK." And not enough coolness under fire to sit down quietly and come up with their own plan in time for the 6 O'clock news. Something really unexpected, from out of left field(!) And we know May looks utterly out of her depth when that happens: so, an opportunity to score heavily. Instead, yet another in the line of prostrate Parliamentary performances, kowtowing to the Empress. "The real fight starts now" -?
Abject. Pathetic. Deserving of utter oblivion.