I used to be a Presentist but now that's all in the past

Bill gets 2013 off to a flying start with a revamp of a late 2010 posting on presentism.  If he carries on like this I'll have plenty to comment on, though I'm a bit concerned for my blood pressure.

I'm not sure what the thesis of presentism is.  I took it to be the common or garden notion that Bill gets close to in the following:

He [the presentist] seems to be operating with a metaphysical picture according to which there is a Dynamic Now which is the source and locus of a ceaseless annihilation and creation: some things are ever passing out of being and other things are ever coming into being. He is not saying that all that is in being is all there ever was in being or all there ever will be in being. That is the lunatic thesis of the present-moment solipsist.

The presentist can be characterized as an annihilationist-creationist in the following sense. He is annihilationist about the past, creationist about the future. He maintains that an item that becomes past does not lose merely the merely temporal property of presentness, but loses both presentness and existence. And an item that becomes present does not gain merely the merely temporal property of presentness, but gains both presentness and existence. Becoming past is a passing away, an annihilation, and becoming present is a coming into being, a creation out of nothing.

I wouldn't want to talk about the temporal property of presentness.  It's too easy to slide into nonsense like Julius Caesar possesses the temporal property of pastness.  But let's put that quibble to one side.  Bill says that to be a substantive philosophical thesis presentism must avoid the trivial.  To that end he puts words into the presentist's mouth.  Examples:

1. [James, the actor] Dean does not presently exist at all
2. Dean does not presently exist at any time, past, present, or future.
3. It is presently the case that there are past times at which Dean does not exist.

For me, in (1) the presently and the at all are  redundant, but Bill insists one or both must be there to avoid triviality.  Bill then elaborates (1) into (2).  What can I say about this?  I suppose one might say this for a joking, exasperated kind of emphasis, but it's nonsense, isn't it? What could it possibly mean to say that Dean does not presently exist at any time in the past?  It's an absurd jumble of tenses.  Compare with Dean does not presently talk at any time in the past.  Finally Bill claims that (3) follows from (2).  You've heard of GIGO?  This is NINO.  (3), though, is not too distant syntactically from something  a presentist would say, viz,

4. It is presently the case that there have been past times at which Dean did not exist.

Explaining the quantification over time in (4) is interesting but will have to wait for another day.  In the meantime  I'm happy to run aground on the Scylla of triviality.