hoppy2B
You have some interesting ideas about brewing (have to have a chat about why anyone would want to steep hops at 67oC as you proposed in the Spitfire recipe thread).
Steeping grain rather than mashing can be useful, but you have to pick your malts carefully. In most cases if you are trying to convert an AG recipe to an extract version its smart to do a mini mash if you are looking for much from specialty malts.
Some modified malts do yield a fair amount of colour and flavour from a steep, often quite different from what you would get from a mash.
There is little if any point in steeping Base Malts and remember that Munich is a base malt. Most of the information available on cold steeping is in the home brew literature, rather than in professional publications. There are used for cold extraction in malt quality analysis but the closest I can find to anything well quantified is some work done at
Briess (well worth a read).
Based on what it shows to get an equivalent amount of extract from Munich you need to use 4 times as much to get the expected mass of extract, but that would give you roughly 4 times the colour... for light crystal it about double for the same outcomes.
Steeping grain is potentially a useful technique but I would want to see people put a fair amount of thought into just what they are doing and trying to get from the process.
Note that the results above are from a 24hour steep at 20oC, if you are steeping for a short time I doubt anyone is getting anything like the yields above.
Doing a hot steep (hot enough to gelatinise the starch) without mashing will put a lot of unfermentable starch into solution inevitably adding haze to the beer, cold steeping will give most of the colour but who knows what else.
For mine much better to do a mini mash.
Mark