Let me try to clarify this for you.
The issue here is nothing to do with digital nor HD - it is entirely to do with encryption - in this case, of pay TV channels. Providers like Dish are using standard DVB-S/S2 to transmit the digital TV, any DVB-S/S2 card can receive and demux these signals directly into any TV capable media centre like LMCE. However, because access is controlled due to the majority of channels being pay TV, the content itself is encrypted. The only ways to decrypt the content is either with a CAM/CI decryption module from Dish plugged into your DVB card (this is a part of the DVB standard) or by getting an equivalent card from somwhere else. The latter is, of course, of dubious legality. However, not of morality assuming you are paying for the same service anyway. Either way, we cannot discuss that option here - you will need to look into that yourself!
Forget the digital component thing - no idea what that is, but "digital" and "component" are almost mutually exclusive in that there is no point in splitting a digital feed into components. I think you may have misunderstood some other technology. Either way, it isn't relevant here.
"push full HD content" across a LMCE network is not accurate, nor what I was saying. Put simply, HDMI is an uncompressed video stream - it isn't intended for video network transport, storage or distribution, so rather than go to the effort and expense of compressing it (lossily) sending it from your receiver/BD unit to your TV and then decompressing it again, it is left uncompressed and sent as is, because there are no disadvantages to doing so, and it saves money on hardware and retains identical quality. However, you are talking about taking that stream and using for "network transport, storage or distribution" and so you will encounter the disadvantages of not using HDMI for the designed purpose. Primarily, a single HD (1080i60) stream consumes approx 1.5Gb/s. The maximum practical throughput you get from a gig network is around 300-350Mb/s, or 5x too slow.
If you can get the DVB and decryption done inside a LMCE box, then you can take the compressed video stream and redistribute it to any LMCE MD you wish, typically consuming 12-15Mb/s per stream - in otherwords you can do several simultaneously with a gig network. Decompression only happens once the stream reaches the intended MD. A very common example of this is FTA (Free To Air) DVB and ATSC digital TV channels are almost always unencrypted, and so many people on these forums routinely pipe HD TV channels across their LMCE network (including myself). And if you can find a provider that will allow you to decrypt on your own hardware, then you can do exactly the same with cable and satellite channels - ie not a technical issue, a commercial one.
The same is true of BluRay and HD-DVD - the issue isn't technical, its commercial, getting the facility to decrypt on our own hardware (the LMCE boxes in this case). The only way around this currently is how LMCE does it, and it is very limited - it rips the disks to HDD first, then plays and decrypts as it goes from the HDD. But again, it only decrypts at this point, it doesn't decompress until the stream has reached the intended MD. So, similarly, you can play a BD/HDDVD disk from one machine across the network to another. In this instance the bandwidth required is upto around 36Mb/s, from memory.
Getting from para 4 above to para 5 above, ie from an uncompressed stream from an HDMI port into a compressed stream such that it is practical to send across the network, would require the heavy duty hardware I was talking about. It exists, but to make it financially practical, you will find that the quality of compression is pretty poor.
One final point, you do not necessarily need digital for HD. Analogue component connections are perfectly capable of at least 1080i60, this is quite common in Home Theatres that don't use HDMI. You could potentially use an analogue HD capture card that has component in. Still not as good as doing all the work inside the LMCE box, but an alternative.