Mooner, :!:
Your post is a bit strange, not to mention incorrect. Not only that, you are oddly confident in the merits of your false info. 8O Just what do you think will happen by feeding the food directly to the fish? I've been keeping fish for the better part of 20 years, and I've yet to see or hear about a problem. It depends on WHAT you are feeding! Some fish like angels do well at picking apart the frozen chunk if it's secured with something. Other fish are so large that they just gulp it down whole. In other situations, depending on what fish are kept, it's best to disolve the frozen food first. Letting a whole chuck of frozen food drift around a reef tank also benefits microinvert populations - as is evidenced by my 2 year old, fat and healthy mandarin. It's not the thing to do every time, in every system, but there is a place for it.
Please refrain from making "I'm not sure why it's wrong, but it is" kind of posts. :roll:
Regards
Jim