I tend to compeltely agree that the average off the shelf main girdle does little more then help hold stuff 'together' once it fails.
I do however see times where a PROPERLY engineered and installed girdle can be of help when you have no choice such as in classes where the output tends to cause cracking in the webs around the main bolts but you are forced to use a stock block. Bottom line is trying to locate the cap. Tolerences are too large on mass produced engines and OEM materials are not up to the job. Aside from good 'shouldered' or doweled studs (machining required), caps of sufficient strength (both can help the block), more 'bolts' and splaying, I can see where and FE can benefit. They are know to crack when pushed above 600HP or so (I am sure many of done it with out failure so no need to let me know!
). What the FE has going for it is the skirts. Just like they crossbolted the 427 to help, a proper girdle can tie the caps too the skirt, but in all directions. Like was said earlier, it doesn't make the block stronger, just likely to live longer by reducing cap walk or fretting (just like our motors don't suck air in, atmospheric pressure forces it in). Pull a cap and it is easy to see if it is walking on you by looking at the mating surface. Be sure and listen to the point about it all must be machined to work together or you will be sorry!
But then again, I am not an engine builder
