'Winter Banana' Apple as Rootstock for Pears?

Many fruit tree hobbyists have heard that the 'Winter Banana' cultivar of apple is unique in its ability to be graft compatible with pear.  To this end, the majority of references I've found are anecdotal.  While a fair number of people have claimed success, many appear to have created these intergeneric grafts no more than a couple of years prior to sharing their findings with the internet.  This leaves me wondering what the long term survivability rate is with these unions.  

I was able to find one long term study spanning 11 years (https://eurekamag.com/research/007/637/007637340.php) which covered using 'Winter Banana' as an interstem between pear scions and clonal apple rootstocks.  For pears two different cultivars were trialed, while five (or six?) clonal apple rootstock selections were used as a base in all possible combinations.  Of note is that the survival rates differed according to pear variety, but what was consistent was that there was 0% survival when pear scions were grafted directly to any of the apple rootstocks in the trial.  The only successful grafts were when the 'Winter Banana' interstem was used between the apple rootstock and the pear.  However, simply using a 'Winter Banana' interstem was not enough to assure success for every apple rootstock.  By the end of the study survival rate varied from good on M. 26 rootstock with interstem to complete failure for M. 9 rootstock with interstem.  Additionally, of the surviving trees, only those on certain rootstocks were able to still produce fruit.  

From this trial combined with various anecdotes from hobbyists, it is clear that 'Winter Banana' does have ability to negate incompatibility issues between at least some pears and some apple rootstocks.  However, what's missing is trial info on what would happen if the otherwise incompatible rootstocks are completely removed from the equation.  What would happen if 'Winter Banana' growing on its own roots were used as a rootstock for pears with no incompatible apple rootstock attached to the tree?  I hypothesize that this would lead to a drastically higher rate of long term survival and ability to maintain fruit production.

I can only assume that this latter experiment has not been tried simply because 'Winter Banana' (and almost all apple cultivars for that matter) are not commercially available on their own roots.  At this time the only way for someone to get an own-root 'Winter Banana' apple tree is to create it themselves.  Well, I hope I will be able to change that.  I am currently working on creating a stool bed where I can among other things produce a handful of own-root 'Winter Banana' trees each year (if all goes well, maybe I'll have some available beginning as soon as 2024).  While my primary reason is to produce them to be full size own-root apple trees (it's a good winter storage variety so having it in large tree form is a great idea), this would also provide myself (and maybe others) with an opportunity to play around with this intergeneric grafting to see what could become of it!