Andy,
a big fight is going on in Italy these days about the same issue.

There are several approaches. One is to let disciplinary scientific societies build their own ranking for disciplinary journals (I leave out the even tougher - but clearly relevant for HET - issue of classifying books). Another is to simply stick to purely bibliometric indexes, like IF or h-index. A third is to grant (and fight for) a presence in each tier to each discipline: say, one spot for HET in the top tier of journals, two spots in the second tier, etc.
  
The first approach would be largely preferable, provided scientific societies do their job reasonably well. The problems arise from the possible presence of vexed interests plus the open hostility of mainstream economists against a solution that, to their view, would water down the whole aim of the assessment exercise. 
The second solution is the most likely to be selected, but is obviously very penalizing for HET.  To my view, it is nonsensical even for mainstream economics (there are hundreds of scientific works testifying the folly of using bibliometrics in general, not to mention for assessing heterodox approaches or, even worse, individual researchers). 
The third one might be a good compromise, but of course it hinges crucially on who, and on what basis, is making the selection of the top disciplinary journal(s).

The good news for Italian HET is that a historian of economics, Siena professor Alberto Baccini, has become a recognized authority on research evaluation. So he might be the go-to-guy for helpful suggestions.
 
The bad news is that at present there seems to be little willingness on the part of the Italian national research evaluation organization (ANVUR) to listen to the complaints, arising in particular from the social sciences area (with the only exception of mainstream economists) against the blind endorsement of bibliometric techniques.

Nicola Giocoli   
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