As much as Alexander pointed out the three-film problems that could be met, there was no denying the synchronous and advantageous effect that it could achieve if done well.
The entire trilogy is all about Marty Mcfly not being a to catch a break after all. As soon as he mistakenly hopped back in time, his time-traveling course and adventure have been continuous.
When he got back to an improved life in 1985, Doc Brown quickly called him to ride again into the future to correct his future family's downfall.
When he was expecting to go back to peaceful 1985 once again, it has become Biffed with madness.
Then, he had to go back in time again to somewhere in the 1950s to correct the consequences of Biff having the Sports Almanac.
Just as everything was all well and fine, Doc Brown got lost in time by the end of the almanac problem and through a series of events, Marty travels with the DeLorean once again.
Then, the Eastwood persona and Doc Brown's love interest debacle happened to end with poor Marty finally catching a break and reuniting with Jennifer to a much favorable 1985.
The entire film is continuous, synchronous, and intricately linked that the most logical way of producing it should be all at once.
If everything is up to schedule, then the massive four-year gap to such a not-so-far apart narrative would be corrected.
The people who loved the first movie would not be so alienated when Marty and Doc's adventure is so far off into four years of their lives.
A much suitable theatrical release is just the start of such an advantageous filming schedule.
When considering the clear aging and change that the actors and actresses would go through, having everything filmed at once would solve that problem.
Even the possibility of complications such as actors quitting and not being satisfied with their pay would effectively be mitigated since they'll be asked to sign all three films at one go.
There would be no such things as flakers and egomaniacs that would back out on a contractual obligation to finish all three films.
For Alexander, who was quite observant, he is among the ones who were quite discomfited with the clear change of the actors.
Jennifer has changed faced, Marty and Doc Brown's actors had clearly aged even though supposedly not much time had passed. Integral George McFly was reduced to a prosthetic-faced man with a back problem to hide the fact that they didn't get the original actor back.
If the bulk filming works out well, such a disjointing detail problem would be gone, and Back to the Future would be even more pristine than what it had been in.
An added advantage to such a three-fold signing is the fact that the actors can't ask for incredulous pay raises.
They still don't know how the film would fare in the theaters after all and before they realized their "worth', Creed Pictures has already sealed them in with a reasonable paycheck.
Every film is a risk and a single break-out success would inflate many entitled actors to think that their integral role in that success could not be replaced.
3 films at once may be quite taxing on the budget but it also saved up on a lot of paychecks that would balloon the production cost further.
The paycheck savings won't just confine themselves to actors but to the production crew as well.
The general rule of Hollywood talent payment is incremental raise to every success and pay decrease to every lose after all.
Aside from the workers that are paid with set prices, all the filmographers that felt they need more money could only choke it up as they still had no idea whether the 3 films they've worked on would win or lose.
So, the overall budget of the trilogy has been reduced quite significantly. Creed Pictures essentially just has to pay more now to save up in the long run.
Even Zemeckis and Gale may have asked for their agents to tone down on their talent fee for this reason. Besides, they are probably more than happy to be able to work on their passion project that had been rejected 40 plus times by doubters.
Rob and Bob should be quite grateful for Creed Pictures for picking up their discarded dreams. The old Creed just had to pull them over and worked on aiding them while the little Creed gave them an already concrete idea before they had even begun to refine their draft.
The sciptcrafting problems that Alexander had pointed out as the biggest downside for the version in the original have also been solved.
There was no point worrying about many script iterations when Alexander himself has already given the mist-drifting Rob and Bob directions to where they would go to.
As for the issue with special effects, it is a factor that has a set price for each frame it is used, so a budget could just be thrown into it to make things happen.
Besides, ILM is only supplementary to most things and it is up to Innovative Rob to work out most of his innovative filming ideas.
Overall, as many risks and downsides that could be listed for back-to-back filmings, the many advantages are more than enough to cancel it all out.
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Alexander does not doubt that the bulk filming decision was not a spur of a moment thing at all. His grandfather is not that risky to waste everything so that he could give his seemingly infinitely calm grandson a surprise.
Sure enough, Sullivan didn't disappoint at all and had done quite a lot of deliberation before deciding to do what he set out to do.
If Alexander spurred many of the pros and cons in a single calculation session, then old Sullivan could do that better and many times over.
The old Creed was the Creed grand patriarch after all and could be considered to be the grandmaster of Creed calculations. As narcissistic as the old man is to even name a prevalent business strategy as Creed, Sullivan's skill and talent of business assessments and cost-efficiency could not be denied.
Every filming problem that his 3 film productions would encounter had probably been laid out on a board and Sullivan had dutifully made every possible solution for them.
Even the many upsides and downsides of bulk filming strategies could have been improved and tinkered on by the business-savvy old man.
Sullivan was a business tycoon who turned his skills to film management for survival after all.
Alexander could more or less tell that the old Creed didn't hesitate for long to give his greenlight for back-to-back filming of the Back to the Future trilogy.
As crazy things may seem, it won't stay crazy for long if one deliberates and fine-tunes it. As much as Alexander doesn't show much emotion towards his grandfather, there was no denying that he respects the old Creed for being to do just that.