The Dif. between a BP and a Rollover is a BP can be shot at a slower speed and be efective and the rollover must be very fast or your toast.
I have to disagree with your quick conclusion there about any typical BP and any typical Rollover/Snake. I would propose, instead, that, once the ball is securely pinned in initial firing position, the three major types of both the BP and the Rollover share very similar characteristics.
I have observed three basic types of both BP (mid 70s to 80s tour quality) and Rollover (90s through today). The most common one would be type (A) or the longer back & forth shuffle, then the second most common, type (B) or the standstill or very small wiggle set, and lastly the mixed and less common one, type (C) which is the walking dribble back and forth shot.
The most common type, the type (A) fastlongshuffle on the pin, whether BP OR Rollover, which can go rolling the ball under the pin from end to end of the middle 3bar's (#32man) foot, seems easiest to shoot 3/4 and long or even dead bar square shots with. The higher the skill level, the more the ball is rolled back & forth at the same pressure and is generally a rhythm or timing shot. The more quickly and smoothly the ball is rolled back & forth, the faster the ball can be released in rhythm and simply hit at the point desired. This type (A) shot, whether using a BP or a Rollover, seems the easiest to get into rhythm with, no matter how warmed up or cold the shooter is. By nature, feel for the ball increases. Best shutdown defense on both the BP and Rollover fastlongshuffles, of course, is a zone or post defense, which continuously defends against a timed shot that can hit even either extreme long, since it's for the most part a timing shot.
The second most common, type (B), or standstill/small wiggle shots, are also widely seen. There is no natural workup into a rhythm, so keeping the perfect pressure on the pinned ball and keeping the takeoff correct from a standstill or near standstill wiggle is harder. These shooters need more warmup, but can be just as deadly once they figure out the proper pressure and pitch or angle of take off, (also a factor when doing a palmroll push or pull off a pinned ball). The quickset into a hard spray from just past the big dot or at the 3/4 going to the long hole is one of the deadlier features of this shot, while the long long square or deadbar is a bit more problematic to control. A long square or deadbar from these standstill/wiggle BPs or Rollovers are as hard to do if not harder than with a palmroll frontpin. Usually the type (B) shooter will have a very very good pull or push side square or deadbar, but not both. Bait and Race D's usually work better against these BPs and Rollovers, because they are faster, but are usually not as superlong as those from the type (A) fastlongshuffle shooters. Type (B) BP and Rollover shooters are often trying to simply get around the outside 2bar or goalkeeper defender, just as one often does when shooting a standard pull, push or pushkick underrod shot (non-pinned). The best type (B) shooters also seem to have developed really really hard release or firing strokes, which of course minimize the spray from long-rolled balls.
Less common BPs and Rollovers are the type (C) dribble and wiggle shots, although some of the best seem to be of these type. These use the sometimes hard and loud dribble to walk the ball in front of the goal mouth, trying to find the nearest baited hole, or even working the zone or race D into pauses. These BP's and Rollovers, especially at the highest skill levels, make use of the walking dribble to get into rhythm, too, much as the type (A) fastlongshuffle shooters do on the pin. But the feature of an instant quickset, as seen with type (B) standstill or wiggle shooters for very very short sideways pitches is also available. This type of BP or Rollover shooter can walk until just inside or outside either the 2bar or goalkeeper player, stop or continue dribbling at will, and do an instant quickset into a hole a ballwidth or less over, just like the type (B) standstill shooters do, but of course from a much smaller lateral distance, which keeps the natural spraying tendency down versus the type (B) shooter going long but spraying more. More fakes, especially loud tapping ones, are also built-in to these BPs and Rollovers, and most of these type (C) dribble and wiggle shooters can always fall back on their basic BP or Rollover series, the type (A) or type (B) they probably began shooting pinned shots with. Defending the type (C) is usually best with observing which short quick shot holes they favor, baiting these holes and closing them. Although I have seen that some can go from a walking dribble with a BP or Rollover to very far over to the other side successfully (more than half goal length). But they usually cannot hit these as well as the baited holes, which are simple 1 inch longs or shorter, to either pull side or push side or splits.
I've observed these over the past 20 years for not just BPs and Rollovers, but guess which shot uses type (C) strategies with stops and starts, quick sets and crossover fakes? Why the Euro, of course... but I think for Euros, the type (C) dribble-wiggle is an even more common choice, seen in perhaps half if not more with most Euro shooters, at least at the pro or tournament levels I've seen.
BP purists should be rightfully proud of their skill levels, with the ball control to nicely hit picked holes in rhythm, negating the need for brute speed, but fastlongshuffle type (A) Rollover shooters exhibit the same accuracy and precision, and most non-Rollover shooters just don't realize why absolute squares and super 7 deadbars from these shuffling snakers OFTEN SEEM SO IMPOSSIBLY EASY. It's because they're not having to crank the ball sideways while maintaining control, and the ball is in motion already, just needing to be released in its final direction.. SAME AS A RELEASED LONG BALL ON A BP. And the roll once released can be plenty fast, not quite as fast as the type (B) standstill/wiggle lateral, but as fast as when you flick the top of the ball with your fingers to roll it, which can be as quick if not quicker than smacking or pushing/pulling the ball from the side. That can actually hurt your finger.. LOL!
Of course, in closing, one cannot emphasize enough that at the release or firing point, the good shooter still must have enough forward rollover or BP cranking speed, which would be the second consideration after the initial pitch or launch from whichever type (A), (B), or (C) BP or Rollover that the shooter is coming from. And at this point, speed to the hole is also helped when shooting from a Rollover or Euro front pin, being several inches closer to the goal at contact. But if the BP shooter is smooth enough and the D isn't zoning/posting D a shuffle, or the D is prone to too many pauses checking the shooter's motion, any decent firing speed is usually good enough, too. The BP longer swing, on the other hand, also means a longer time of contact with the fired ball, the same as with a normal pull, push, or kick shot.
Hope my 20 pesetas can illuminate the SIMILARITIES, not the DIFFERENCE of the various pin shots ... Or which one was superior or better. The most difference I can see is that closed hand Euro's, BP's, pulls, pushes, and kickshots are predominantly stroked shots, like batting for hits in baseball, or with irons in golf. While almost all open hand, palm rolled BP's, Rollovers, and Euro's are more like slap shots in hockey or swings for homers in baseball.