Board Thread:Warhammer 40k General Discussion/@comment-69.143.134.163-20150419161351/@comment-8881468-20150522120125

If you define using the canon material at hand with regards to the issue at hand as being unreasonable, you got me...

The problem is that GW already did make definite comments about that in "the unremembered empire" where Guilliman goes on abhout the lack of any form of codification that could turn a force of space marines from several legions into a united fighting force, If I remember correctly, he even goes so far as to name it "unprecedented" but the quote is around on this forum and I can dig it up again from the book with no problem.

We also have the definite statement of gene-seed being unique and recognisable as in "deliverance lost" we also know that no apothecary operated on changin the gene seed until fabius in the onset of the heresy (aka when both legions were already gone for decades)

We got Scars with the exchange of neophytes and the resultring loyalty problem ;)