i'm still able to send 'old' TRC coins, and see them included in later blocks.
Any chance you can extract the full reject reason from your log file ? (the client log, if you were solo-mining) ; could be some time-sync issue, or your local client/daemin just "saw" the new block too late.
(looks like cgminer output)
There is no reason why a 51% attack needs to affect txns. It can just monopolize mining and have no other impact on end-users. (i.e. unapproved miners get their blocks rejected. other than that everything is normal)
Yeah, you're right, i guess it's because i won't necessarily first prevent other from mining, if i were attacking...
Anyway ... the "tiny, micro, small" pool i've been mining on from time to time found two blocks in the last 24 hours, but .. currently, that pool hashing power is really low, less than 500 M hashes /s

not unusual then...
i'll wait and see if another one is finally found by this one