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Re: [IMP-dev] Failure rate of restraints

Of course, but rescaling different parts of the forcefield by different
amounts (e.g. bond terms vs. torsions, since the latter act on twice as
many atoms) will really break things, and that was what I read your
proposal as.
Sorry if I was unclear. I would consider a FF a single restraint as it doesn't make sense to mix and match the terms (the fact that it is implemented using other things is an internal detail). I also explicitly excluded them since they are not satisfiable restraints (there is no sense of fit/not fit with a raw force field). Further, you can't really use a FF far from a good configuration and when you are close to optimum, the scaling issues don't matter so much (since all the satisfiable restraints must be near 0 anyway).

Molecular mechanics people have worked with such nonbonded interactions
in their forcefields for many years: the effects of such cutoffs on the
energies and dynamics are well understood. I don't think the same could
be said for a rescaled term. This is why I suggest rescaling terms such
as EM and SAXS rather than sterics and nonbonds.
As far as behavior is concerned, it doesn't make any difference whether you rescale one or the other as either one can be used to give the same shaped energy landscape.