One reason why any "Catch 22" case would be particularly hard to make (pace the signatories to the petition Extropia DaSilva cites) is surveys.

Whether it's 2dF, SDSS, 2MASS, IRAS, DENIS, WMAP, .... these huge surveys are fully public - even the raw data is available (in many cases).

Anyone - when developing an alternative cosmological theory or not - can get these survey data, for free! (you will need a broadband internet connection, and you may need to live in North America, the EU, Australia, Japan, ....)

This data is very much richer and better than anything available only a few decades ago - deeper, more consistent, more wavebands, errors much better characterised, ....

Further, ALL HST data - including the raw data - becomes available after a proprietary period (6 months, a year), and for much of it (HDF, UDF, ...) the proprietary period is 0 days.

With such a huge wealth of high quality data available, for free, what more could anyone developing an alternative want?

Maybe they want computing power? A top-of-the-line, out-of-the-box PC today has computing power that astronomers only 25 years ago couldn't have even dreamed of, much less bought. And with science grids like BOINC, and the widespread, free, availability of the underlying grid protocols, anyone developing an alternative, with a need for really heavy-duty computing, could have it - I'm sure the PCs of the signatories to the petition, plus those of their friends and relatives would make a big dent into any computing project.

So what, in fact, is the Catch 22? A paying job at a university?