I suspect that with regards to 4e, even if a DM does not have Climb stats written down for a specific monster, the DM will be able to determine it without just making something up. But this is a playstyle preference, and completely subjective. If one needs to know that Monster X has a +32 climb check from 18 ranks, +2 synergy, +4 racial, +4 items, +2 sacred bonus, +2 miscellaneous, that's a valid way to play. But objectively, that's very complex. So it's possible there might be simpler ways of reaching a similar result, without necessarily invoking rule 0 or DM fiat (which, by the way, are also valid ways of playing.)