[Nibile]

i had a long lay off in summer 05.
got injured in mid july and was off til october, with lots of phisio though.
at mid november i was already catching up, but the most difficult thing has been regain confidence in doing precarious moves or dynos, or anything really hard for me anyway.
in january i was very ok.
i think what helped me alot has been doing some light wheights, in order to make 4 sets of 25 reps for each muscular group. you lose fat, and you enhance the quality of the muscle, without gaining wheight.
and, moreover, you rip on da beach.

[moose]

From what I've read, you lose your most fully trained worked attributes the slowest.  So boulderers will tend to retain quite high finger strength even during an extended period off... although any poorly developed stamina will have plummeted rapidly back to its even more paltry baseline.  The odd layoff of a few weeks probably has little effect overall: some physical recovery gains ("microtears" heal a bit etc) but a few sessions might be needed to get back into the groove and enjoy the benfits.

Re extended lay-offs... all it not lost.  There's a much cited example of Moffat taking almost 2 years off with shoulder injuries... people doubted he'd ever come back at anything resembling his previous level.  He supposedly astounded everyone by quickly redpointing several climbs at what was then the highest grade achieved.  I vaguely recall they were a load of Buoux classics - he did something like 3-5 of them at a time when that was about the total number of people climbing at that grade!  The sports science books all seem to ascribe it to a "purging" of inefficient muscle memory sequences / engrams - the time-off had given his body time to rid itself of kinaesthetic whackness.

[Paz]

I basically take a lay off until I'm bored with being injured, feeling sorry for my self saying `rest' `patience' and all that shite.  Psyche has to come out somehow.  Eventually I just have to climb again, luckily there's always something I want to do.  But even away from intentionally easy climbing, I've been worried about my fingers before both Pembroke trips' this year and they were the best ever.   But then I always was primarily psyched for trad jug pulling.  I had another painful twinge the other day and I'd echo dave's implied advice about not laying off therabands.  If you've spent years imbalancing your shoulders they won't rebalance in a few weeks of not climbing. 

Climbing's a broad enough sport that you can't possibly have to lay off it all.  There's always aid, winter or snow plods.  But even if they're too tiring and embarassing then, there's a lot of slabs in the world and Dawes invented one handed climbing during a shoulder inflicted lay off. 

[Control freak]

You will probably come back stronger. Most people do after a lay off. And Psyced!

Jerry Moffat. Pappy Onsight. No further questions...

[Doylo]

I remeber reading that Mooney had six months off once, did a month of bouldering and then went and made a early ascent of Cry Freedom at Malham. Talk about natural stamina!

[Ru]

I bet the month's bouldering involved doing endless endurance circuits at Tom's roof and cragx rather than a couple of sessions at the Plantation.