clause inital σήμερον in Luke 23:43

I have seen arguments which claim that Luke prefers a post verbal position for σήμερον with an unstated implication that we can make exegetical judgments based on a microscopic sample of textual evidence. If Luke has a hand full of post verbal examples of σήμερον that might suggest reading the clause initial σήμερον as marked in some way. For example:

Luke 19:5 καὶ ὡς ἦλθεν ἐπὶ τὸν τόπον, ἀναβλέψας ὁ Ἰησοῦς εἶπεν πρὸς αὐτόν· Ζακχαῖε, σπεύσας κατάβηθι, σήμερον γὰρ ἐν τῷ οἴκῳ σου δεῖ με μεῖναι.

Luke 23:43 καὶ εἶπεν αὐτῷ· ἀμήν σοι λέγω, σήμερον μετ᾿ ἐμοῦ ἔσῃ ἐν τῷ παραδείσῳ.

In both cases we could argue that σήμερον was moved forward to mark salience. σήμερον is a movable constituent and clause initial movable constituents are often marked for salience. The sample is so tiny, it is best to avoid any sort of strong claims based on Luke's word order.     

A while back Iver Larsen demonstrated that the solemn saying introduction formula:  [ἀμὴν] ἀμὴν λέγω σοι, [ἀμὴν] ἀμὴν λέγω ὑμῖν, ἀμήν σοι λέγω,  never takes and an adverb, not any sort of adverb. I searched TLG-E for λέγω σήμερον from Homer to 1st Cent. AD and found one example, Luke 23:43.

The Hebrew idiom represented in the LXX with διαμαρτύρομαι ὑμῖν σήμερον or ἀναγγέλλω σοι σήμερον, doesn't really apply to the [ἀμὴν] ἀμὴν λέγω σοι formula. These are different idioms.

Deut. 4:26 διαμαρτύρομαι ὑμῖν σήμερον τόν τε οὐρανὸν καὶ τὴν γῆν ὅτι ἀπωλείᾳ ἀπολεῖσθε ἀπὸ τῆς γῆς εἰς ἣν ὑμεῖς διαβαίνετε τὸν Ιορδάνην ἐκεῖ κληρονομῆσαι αὐτήν οὐχὶ πολυχρονιεῖτε ἡμέρας ἐπ᾿ αὐτῆς ἀλλ᾿ ἢ ἐκτριβῇ ἐκτριβήσεσθε

Deut. 8:19 καὶ ἔσται ἐὰν λήθῃ ἐπιλάθῃ κυρίου τοῦ θεοῦ σου καὶ πορευθῇς ὀπίσω θεῶν ἑτέρων καὶ λατρεύσῃς αὐτοῖς καὶ προσκυνήσῃς αὐτοῖς διαμαρτύρομαι ὑμῖν σήμερον τόν τε οὐρανὸν καὶ τὴν γῆν ὅτι ἀπωλείᾳ ἀπολεῖσθε

Deut. 30:18 ἀναγγέλλω σοι σήμερον ὅτι ἀπωλείᾳ ἀπολεῖσθε καὶ οὐ μὴ πολυήμεροι γένησθε ἐπὶ τῆς γῆς ἧς κύριος ὁ θεός σου δίδωσίν σοι εἰς ἣν ὑμεῖς διαβαίνετε τὸν Ιορδάνην ἐκεῖ κληρονομῆσαι αὐτήν

Nor does the Acts 20:26 μαρτύρομαι ὑμῖν ἐν τῇ σήμερον ἡμέρᾳ ὅτι have any bearing on [ἀμὴν] ἀμὴν λέγω σοι formula. Once again these are completely different idioms.

Acts 20:26 διότι μαρτύρομαι ὑμῖν ἐν τῇ σήμερον ἡμέρᾳ ὅτι καθαρός εἰμι ἀπὸ τοῦ αἵματος πάντων·  

I would conclude from reviewing the main arguments about σήμερον in Luke 23:43 that Iver Larsen's observation about the lack of an adverb with the [ἀμὴν] ἀμὴν λέγω σοι formula is decisive. 

Luke 23:43 καὶ εἶπεν αὐτῷ· ἀμήν σοι λέγω, σήμερον μετ᾿ ἐμοῦ ἔσῃ ἐν τῷ παραδείσῳ.

... let me take a look at the phrase AMHN (AMHN) LEGW hUMIN/SOI ...

In all the 75 occurrences a qualifying adverb is never added, SHMERON or any other. This, to me, is very compelling evidence. To add SHMERON to "I say to YOU" is not only redundant, but unprecedented. On the other hand it makes good sense to have it included with MET' EMOU ESHi EN TWi PARADEISWi. Not only will Jesus remember the criminal some day in the distant future when he comes in his kingdom as the criminal had asked for, but already SHMERON he will in spirit join the spirit of Jesus after death in PARADEISOS.

Joining σήμερον with λέγω in Luke 23:43 fails on the basis of relevance. Attaching σήμερον to λέγω increases the processing effort without offering any useful additional information.