# Gavin Andresen
# 2011-08-23 22:51:42
# https://bitcointalk.org/index.php?topic=38932.msg476510#msg476510

You're right, I think even without blockexplorer Satoshi would've added the IsStandard() check.  There were a series of "oops, didn't think of that" moments that pushed him to disable a bunch, tighten up some requirements on existing opcodes, and add IsStandard(). @p{par}

In general, I believe in "whitelisting" instead of "blacklisting" to try to prevent harm. Enable functionality that you can prove (or convince yourself beyond a reasonable doubt) will not cause problems. I'm strongly influenced from watching web content systems that fail repeatedly trying to detect malicious HTML or CSS. @p{par}

RE: allow non-standard transactions but give them a very low priority so they take a very long time to confirm:  I like that idea.  I'll have to think a little more about possible unintended consequences (will they tend to fill up transaction memory pools and crowd out low-priority standard transactions?  Do they need their own memory-limited pool?  etc) @p{par}

The intent was always to relax the rules when SPV/headers-only mode was implemented and non-mining clients didn't need to download the entire block chain.  However, nobody tackled that work (it is on my TODO list, right after I tackle some testing framework work).